Cartesian Coordinate System
Last Updated :
10 Jun, 2024
Cartesian Coordinate System in Maths is a division of coordinate geometry where the location of a point in a plane or space is marked by a pair of numbers or three numbers. The branch of geometry that deals with the Cartesian Coordinate System is called Coordinate Geometry. The numbers which are used to identify the location of a point in a plane or space are called coordinates.
The concept of the Cartesian Coordinate System is fundamental for class 9 and class 10 students which will later help them to understand various graphs and solve problems in physics.
In this article, we will study about the Cartesian Coordinate System, cartesian coordinates, coordinate axes, two dimensional as well as three-dimensional coordinate systems in detail.
What is Cartesian Coordinate System in Maths?
The branch of Geometry that deals with the labeling of points in space or plane and marking their location with numbers is called the Cartesian Coordinate System. The geometry dealing with the Cartesian Coordinate System is also called Coordinate Geometry. The Cartesian Coordinate System helps draw graphs of various functions and hence is the fundamental concept for the interpretation of analytical geometry and various other branches of mathematics such as linear algebra, calculus, complex analysis, etc.
History of Cartesian Coordinate System
The credit for the development of the Cartesian Coordinate System goes to the French Mathematician Rene Descartes. He published the idea of the Cartesian Coordinate System in 1637. Although several others also worked on this such as Pierre De Fermat who also worked independently on the Cartesian Coordinate System but did not publish his results and findings. Another person, Nicole Orseme who was a French cleric also worked on this before Fermat and Descartes.
The thing that was common to both Descartes and Fermat was that they both used a single axis to represent the variable length. The concept of a pair of coordinates was introduced later. After the discovery of the third dimension, several new coordinate systems such as the Spherical Coordinate System, Polar Coordinate System and Cylindrical Coordinate System also developed.
Components of the Cartesian Coordinate System
The Cartesian Coordinate System is characterized by basically three components. These are Cartesian Coordinates, Coordinate Axes, and Cartesian Planes. Let’s learn them in detail.
Cartesian Coordinates
Cartesian Coordinates are the set of points that are used to identify the location of a point in cartesian space. In a 2D cartesian system, the coordinate of a point is given by an ordered pair (x, y) where x and y indicate the distance traveled in the direction of the respective axis. The x-coordinate is called abscissa and the y-coordinate is called ordinate and combinedly they are called coordinates. In 3D Coordinate Geometry, a point is identified by three points (x, y, z) where x, y, and z are the distance traveled by points in the direction of the x, y, and z axes respectively.
- Abcissa: The value of the x-coordinate is called abcissa. It tells the distance traveled by a point away from the y-axis in the direction of the x-axis in a 2D Cartesian Plane.
- Ordinate: The value of y-coordinate is called ordinate. It tells the distance traveled by a point away from the x-axis in the direction of the y-axis in a 2D Cartesian Plane.
- Applicate: The value of z-coordinate in a 3D Cartesian System of Coordinates is called ordinate. It tells the distance traveled by a point away from the x-axis and y-axis in the direction of z-axis in 3D space.
Coordinate Axes
Coordinate Axes are the reference axes that are used to measure the distance travelled by points. In 2D Coordinate System, there are two coordinate axes X and Y and in 3D Coordinate System there are three axes X, Y and Z.
Note: All the axes intersect each other a point called origin whose coordinate is given as (0, 0) in 2D coordinate and (0, 0, 0) in 3D cartesian coordinate system.
Cartesian Plane
Cartesian Plane is a 2D space or region bounded a pair of coordinate axes in which a point moves. In 2D system there is only XY plane which is divided into quadrants by the X and the Y-axis. In 3D system there are three Cartesian Planes namely XY Plane, YZ plane and XZ plane bounded by the axis that are present in their names.
Dimension of Coordinate System
Dimesion of Coordinate System basically tells about the number of points used to identify the location of a point in Coordinate Geometry. Depending on this there are three types of coordinate system, these are:
- One Dimensional Coordinate System
- Two Dimensional Coordinate System
- Three Dimensional Coordinate System
One Dimensional Coordinate System
In 1D Coordinate System the location of a point is given using one point. In this case the point travels along a line instead of space or a plane.
It is similar to representing a number on the number line. This system was used by Descartes and Fermat to give the concept of Cartesian Coordinate System.

Two Dimensional Coordinate System
In two dimensional Cartesian Coordinate system, the point travels either in plane bounded by two cartesian coordinate axes. In 2D Cartesian Coordinate System the location of a point is given using a pair of numbers called coordinates expressed as (x, y) where x is called abcissa.
It indicates the distance traveled in the direction of x-axis traveled away from y axis. The value of y is called ordinate and it indicates the distance traveled in y-direction away from the x-axis.
In 2D Coordinate system, the coordinate axes divides the cartesian plane in four parts where each part is called quadrant. The quadrants are marked in anticlockwise. The coordinates are in the form of (x, y) for first, (-x, y) for second, (-x, -y) for third and (x, -y) for the fourth quadrant.
The image attached below describes the quadrants and the pattern of coordinates of the points located in them.

Three Dimensional Coordinate System
In 3D Cartesian Coordinate system a point is located in space and its location is given using three points called Coordinates. In three dimensional coordinate system, a point is represented as (x, y, z) where x, y and z represents the distance traveled by points in the direction of respective axis.
The value of x is called abcissa, value of y is called ordinate and the value of z is called applicate. In 3D coordinate system the space is divided into 8 parts each called octants. The coordinates of the points located in these octants are given as (x, y, z), (-x, y, z), (x, -y, z), (x, y, -z), (-x, -y, z), (x, -y, -z), (-x, y, -z) and (-x, -y, -z).
In 3D coordinate system, if a point is on a coordinate axis then the value of that coordinate is non zero and rest two are zero. For Example, in (3, 0, 0), the point is located on x-axis at 3 units from the origin. If the point is located in a plane then the value of those coordinates are non-zero and the third coordinate is zero.
The image showing a point in 3D Cartesian System is attached below:

How to Plot Points in Cartesian System of Coordinates?
In Cartesian System of Coordinates, to plot a point we measure the distance from the coordinate axes. For this we first need to see the coordinates. Let’s say we have to plot a Point P(2, 3) then we first see that there are two coordinates hence the point need to be plotted in 2D Cartesian Plane.
To Plot the point we first observe the value of x which is 2 and travel 2 units in +x direction. Then we see that the value of y is 3, hence we will travel 3 units from your current position to the direction of +y axis. Thus this will be the require location of the point P(2, 3). Here both coordinates are positive hence the point lies in first quadrant.
.gif)
In case of 3D Cartesian System of Coordinates we start with x from the origin, then move to the direction of y and then to the direction of z-axis. Thus, in case of 3D cartesian system of coordinates point is located in space if all the three coordinates are non-zero.
We know that Cartesian Coordinate System is used to locate points and draw graphs for various algebraic function. Hence, the distance between the points and the equations for the graphs can be written using Cartesian System.
Distance Formula is used to calculate distance between two points, two lines, between a point and a line and many more. The most commonly is used to calculate distance between two points in 2D and as well as three 3D. These formulas are mentioned below:
Section formula is given to find the coordinates of a point which divides a given line in a given ratio.
Consider a line which is formed by joining two points (x1, y1) and (x2, y2) is divided by a Point P(x, y) in the ratio m:n then the coordinates will be given by
x = (mx2 + nx1)/(m + n) and y = (my2 + ny1)/(m + n)
In case of section formula if the ratio becomes equal i.e. 1:1 then it is called Midpoint Formula. Hence, if a Point is mid-point of a line then its coordinates are given as
x = (x1 + x2)/2 and y = (y1 + y2)/2
Slope of a Line
Slope of a line is the inclination of line with respect to the coordinate axes. The slope of a line is calculated as m = Tan θ where θ is the angle between line and the coordinate axis.
The formula for slope of line in cartesian form is given as
m = (y2 – y1)/(x2 – x1)
We know that Cartesian Coordinate System can also be used to draw graph for various algebraic expressions. In this article we will learn Cartesian Coordinate Equation of line and plane.
The standard equation of a line is given by a linear equation epressed as ax + by + c = 0. However there are other forms also in which the equation of a line can be given. These equation are mentioned below:
A plane is a two dimensional flat region bounded by two coordinate axes. The different equations of Plane in cartesian form is given as follows:
Equation of Plane in Normal Form: [Tex]\vec r . \hat n = d
[/Tex] where d is the perpendicular distance from the origin and n is the unit vector on the plane.
Equation of Plane Passing through three Non Collinear Points: [Tex](\vec r – a)[(\vec b – \vec a)\times(\vec c – \vec a)] = 0
[/Tex] where a, b and c are non-collinear points.
Eqution of Plane passing through intersection of Two Planes: If a plane pass through through intersection of two planes whose equation is given as [Tex]\vec r . \hat n_1 = d_1
[/Tex] and [Tex]\vec r . \hat n_2 = d_2
[/Tex] then its equation is given as [Tex]\vec r ( \hat n_1 + \lambda \hat n_2) = d_1 + \lambda d_2
[/Tex]
Cartesian Representation of Complex Numbers
We know that a complex number is given as Z = a + ib where a is the real part and ib is the imaginary part. The letter ‘i’ stand for iota whose value is equal to √-1 which is an imaginary number as there exists no number whose square is a negative number. This is from the law of exponents that any number raised to even power results in positive number always.
In general to represent a number in Cartesian System of Coordinates we take the both axis to be real i.e. numbers on the coordinate axes are real numbers. However to plot a complex number one of the axis usually x-axis is the real axis and the other axis i.e. the y-axis is the imaginary axis. A pictorial representation of plotting of Complex Number is given below:

Application of Cartesian Coordinate System
Cartesian Coordinate System is used in variety of applications. These are mentioned below:
- Cartesian Coordinate System is used to identify location on Earth with the help of latitudes and longitudes. The same concept is used to locate any place on google maps.
- In Engineering especially architecture and civil engineering, Cartesian Coordinate System is used to calculate the distance between places, the line joining the points, the points on the curves and many more.
- Cartesian Coordinate System is used to visualize the algebraic expression by drawing the graph and establish relationship between various variables.
People Also Read:
Cartesian Coordinates System Examples
Example 1: Find the distance between the two points A(-2, 3) and B(3, 1)
Solution:
Here we see that each point is indicated by two numbers. Hence this is the case of two dimensional coordinate system.
Distance between two points in is given as √{(x2 – x1)2 + (y2 – y1)2}
⇒ AB = √{(3 – (-2))2 + (1 – 3)2} = √{(5)2 + (-2)2} = √29 units
Example 2: Find the distance of the points A(2, -1, 4) from the origin
Solution:
Here the point is indicated by three values hence this is a case of 3D Cartesian Coordinate System. In 3D Cartesian Coordinate System, the distance of the point from the origin is given as √(x2 + y2 + z2)
Hence OA = √{(2)2 + (-1)2 + (4)2} = √21 units
Example 3: Find the coordinate of point O(x, y) which divides the line joining the points P(3, 4) and Q(1, 2) in the equal ratio.
Solution:
It is given that O divides PQ in equal ratio. Hence, O is the midpoint of PQ. Therefore by using midpoint formula we have
x = (3 + 1)/2 and y = (4 + 2)/2
⇒ x = 4/2 = 2 and y = 6/2 = 3
Hence the coordinates of the point is O(2, 3)
Example 4: Find the slope of the line formed by joining the points (3, 2) and (-3, -2)
Solution:
The slope of a line is given by the formula
m = (y2 – y1)/(x2 – x1)
⇒ m = (-3 – 3)/(-2 – 2) = -6/-4 = 2/3
Cartesian Coordinate System Class 9
Cartesian Coordinate System is a very important chapter for class 9. Class 9 marks the introduction to graphing linear equations and functions. The Cartesian Coordinate System provides students with the fundamental framework for graphing these equations and understanding the relationship between variables visually.
Cartesian Coordinate System Questions
Q1: Find the distance between Origin and Point P(-3, -2)
Q2: Find the slope of the line joining the points (-1, 4) and (2, -3)
Q3: Find the equation of a line using slope form of a line which passes through point (3,4) and slope is 2/3.
Q4: Find the coordinates of a point which is the midpoint of a line joining the points (1, 3) and (-3, 4).
Q5: Locate Points (-5, 6), (2, -3), (1, 2) and (-1, 0) in Cartesian System.
Similar Reads
CBSE Class 9 Maths Revision Notes
CBSE Class 9th Maths Revision Notes is an important phase of studentâs life when theyâre at a turning point in their life. The reason being class 9 is the foundation level to succeed in class 10. As you know, students must complete Class 9 in order to sit for Class 10 board examinations. Also, it la
15+ min read
Chapter 1: Number System
Number System in Maths
Number System is a method of representing numbers on the number line with the help of a set of Symbols and rules. These symbols range from 0-9 and are termed as digits. Let's learn about the number system in detail, including its types, and conversion. Number System in MathsNumber system in Maths is
13 min read
Natural Numbers | Definition, Examples & Properties
Natural numbers are the numbers that start from 1 and end at infinity. In other words, natural numbers are counting numbers and they do not include 0 or any negative or fractional numbers. Here, we will discuss the definition of natural numbers, the types and properties of natural numbers, as well a
11 min read
Whole Numbers - Definition, Properties and Examples
Whole numbers are a foundational concept in mathematics, encompassing all non-negative integers starting from zero. This set includes numbers like 0, 1, 2, 3, and so on, up to infinity. Unlike integers, whole numbers do not include negative numbers or fractions. Examples of Whole Numbers are 0, 2, 3
9 min read
Prime Numbers | Meaning | List 1 to 100 | Examples
Prime numbers are those natural numbers that are divisible by only 1 and the number itself. Numbers that have more than two divisors are called composite numbers All primes are odd, except for 2. Here, we will discuss prime numbers, the list of prime numbers from 1 to 100, various methods to find pr
13 min read
Rational Numbers
Rational numbers are a fundamental concept in mathematics, defined as numbers that can be expressed as the ratio of two integers, where the denominator is not zero. Represented in the form p/qâ (with p and q being integers), rational numbers include fractions, whole numbers, and terminating or repea
15+ min read
Irrational Numbers- Definition, Examples, Symbol, Properties
Irrational numbers are real numbers that cannot be expressed as fractions. Irrational Numbers can not be expressed in the form of p/q, where p and q are integers and q â 0. They are non-recurring, non-terminating, and non-repeating decimals. Irrational numbers are real numbers but are different from
12 min read
Real Numbers
Real Numbers are continuous quantities that can represent a distance along a line, as Real numbers include both rational and irrational numbers. Rational numbers occupy the points at some finite distance and irrational numbers fill the gap between them, making them together to complete the real line
10 min read
Decimal Expansion of Real Numbers
The combination of a set of rational and irrational numbers is called real numbers. All the real numbers can be expressed on the number line. The numbers other than real numbers that cannot be represented on the number line are called imaginary numbers (unreal numbers). They are used to represent co
6 min read
Decimal Expansions of Rational Numbers
Real numbers are simply the combination of rational and irrational numbers, in the number system. In general, all the arithmetic operations can be performed on these numbers and they can be represented in the number line, also. So in this article let's discuss some rational and irrational numbers an
6 min read
Representation of Rational Numbers on the Number Line | Class 8 Maths
Rational numbers are the integers p and q expressed in the form of p/q where q>0. Rational numbers can be positive, negative or even zero. Rational numbers can be depicted on the number line. The centre of the number line is called Origin (O). Positive rational numbers are illustrated on the righ
5 min read
Operations on Real Numbers
Real Numbers are those numbers that are a combination of rational numbers and irrational numbers in the number system of maths. Real Number Operations include all the arithmetic operations like addition, subtraction, multiplication, etc. that can be performed on these numbers. Besides, imaginary num
9 min read
Rationalization of Denominators
Rationalization of Denomintors is a method where we change the fraction with an irrational denominator into a fraction with a rational denominator. If there is an irrational or radical in the denominator the definition of rational number ceases to exist as we can't divide anything into irrational pa
8 min read
Nth Root
Nth root of unity is the root of unity when taken which on taking to the power n gives the value 1. Nth root of any number is defined as the number that takes to the power of n results in the original number. For example, if we take the nth root of any number, say b, the result is a, and then a is r
6 min read
Laws of Exponents for Real Numbers
Laws of Exponents are fundamental rules used in mathematics to simplify expressions involving exponents. These laws help in solving arithmetic problems efficiently by defining operations like multiplication, division, and more on exponents. In this article, we will discuss the laws of exponent for r
6 min read
Chapter 2: Polynomials
Polynomials in One Variable | Polynomials Class 9 Maths
Polynomials in One Variable: Polynomial word originated from two words âpolyâ which means âmanyâ and the word ânominalâ which means âtermâ. In maths, a polynomial expression consists of variables known as indeterminate and coefficients. Polynomials are expressions with one or more terms with a non-z
7 min read
Polynomial Formula
The polynomial Formula gives the standard form of polynomial expressions. It specifies the arrangement of algebraic expressions according to their increasing or decreasing power of variables. The General Formula of a Polynomial: f(x) = anâxn + anâ1âxnâ1 + ⯠+ a1âx + a0â Where, anâ, anâ1â, â¦, a1â, a0
6 min read
Types of Polynomials (Based on Terms and Degrees)
Types of Polynomials: In mathematics, an algebraic expression is an expression built up from integer constants, variables, and algebraic operations. There are mainly four types of polynomials based on degree-constant polynomial (zero degree), linear polynomial ( 1st degree), quadratic polynomial (2n
9 min read
Zeros of Polynomial
Zeros of a Polynomial are those real, imaginary, or complex values when put in the polynomial instead of a variable, the result becomes zero (as the name suggests zero as well). Polynomials are used to model some physical phenomena happening in real life, they are very useful in describing situation
14 min read
Factorization of Polynomial
Factorization in mathematics refers to the process of expressing a number or an algebraic expression as a product of simpler factors. For example, the factors of 12 are 1, 2, 3, 4, 6, and 12, and we can express 12 as 12 = 1 Ã 12, 2 Ã 6, or 4 Ã 3. Similarly, factorization of polynomials involves expr
10 min read
Remainder Theorem
The Remainder Theorem is a simple yet powerful tool in algebra that helps you quickly find the remainder when dividing a polynomial by a linear polynomial, such as (x - a). Instead of performing long or synthetic division, you can use this theorem to substitute the polynomial and get the remainder d
9 min read
Factor Theorem
Factor theorem is used for finding the roots of the given polynomial. This theorem is very helpful in finding the factors of the polynomial equation without actually solving them. According to the factor theorem, for any polynomial f(x) of degree n ⥠1 a linear polynomial (x - a) is the factor of th
11 min read
Algebraic Identities
Algebraic Identities are fundamental equations in algebra where the left-hand side of the equation is always equal to the right-hand side, regardless of the values of the variables involved. These identities play a crucial role in simplifying algebraic computations and are essential for solving vari
14 min read
Chapter 3: Coordinate Geometry
Chapter 4: Linear equations in two variables
Linear Equations in One Variable
Linear equation in one variable is the equation that is used for representing the conditions that are dependent on one variable. It is a linear equation i.e. the equation in which the degree of the equation is one, and it only has one variable. A linear equation in one variable is a mathematical sta
7 min read
Linear Equation in Two Variables
Linear Equation in Two Variables: A Linear equation is defined as an equation with the maximum degree of one only, for example, ax = b can be referred to as a linear equation, and when a Linear equation in two variables comes into the picture, it means that the entire equation has 2 variables presen
9 min read
Graph of Linear Equations in Two Variables
Linear equations are the first-order equations, i.e. the equations of degree 1. The equations which are used to define any straight line are linear, they are represented as, x + k = 0; These equations have a unique solution and can be represented on number lines very easily. Let's look at linear e
5 min read
Graphical Methods of Solving Pair of Linear Equations in Two Variables
A system of linear equations is just a pair of two lines that may or may not intersect. The graph of a linear equation is a line. There are various methods that can be used to solve two linear equations, for example, Substitution Method, Elimination Method, etc. An easy-to-understand and beginner-fr
8 min read
Chapter 5: Introduction to Euclid's Geometry
Chapter 6: Lines and Angles
Chapter 7: Triangles
Triangles in Geometry
A triangle is a polygon with three sides (edges), three vertices (corners), and three angles. It is the simplest polygon in geometry, and the sum of its interior angles is always 180°. A triangle is formed by three line segments (edges) that intersect at three vertices, creating a two-dimensional re
13 min read
Congruence of Triangles |SSS, SAS, ASA, and RHS Rules
Congruence of triangles is a concept in geometry which is used to compare different shapes. It is the condition between two triangles in which all three corresponding sides and corresponding angles are equal. Two triangles are said to be congruent if and only if they can be overlapped with each othe
10 min read
Theorem - Angle opposite to equal sides of an isosceles triangle are equal | Class 9 Maths
In geometry, an isosceles triangle is a triangle that has two sides of equal length. Sometimes it is specified as having exactly two sides of equal length, and sometimes as having at least two sides of equal length, the latter version thus including the equilateral triangle as a special case. Exampl
4 min read
Triangle Inequality Theorem, Proof & Applications
Triangle Inequality Theorem is the relation between the sides and angles of triangles which helps us understand the properties and solutions related to triangles. Triangles are the most fundamental geometric shape as we can't make any closed shape with two or one side. Triangles consist of three sid
9 min read
Chapter 8: Quadrilateral
Angle Sum Property of a Quadrilateral
Angle Sum Property of a Quadrilateral: Quadrilaterals are encountered everywhere in life, every square rectangle, any shape with four sides is a quadrilateral. We know, three non-collinear points make a triangle. Similarly, four non-collinear points take up a shape that is called a quadrilateral. It
9 min read
Quadrilaterals
Quadrilateral is a two-dimensional figure characterized by having four sides, four vertices, and four angles. It can be broadly classified into two categories: concave and convex. Within the convex category, there are several specific types of quadrilaterals, including trapezoids, parallelograms, re
12 min read
Parallelogram | Properties, Formulas, Types, and Theorem
A parallelogram is a two-dimensional geometrical shape whose opposite sides are equal in length and are parallel. The opposite angles of a parallelogram are equal in measure and the Sum of adjacent angles of a parallelogram is equal to 180 degrees. A parallelogram is a four-sided polygon (quadrilate
10 min read
Rhombus: Definition, Properties, Formula and Examples
A rhombus is a type of quadrilateral with the following additional properties. All four sides are of equal length and opposite sides parallel. The opposite angles are equal, and the diagonals bisect each other at right angles. A rhombus is a special case of a parallelogram, and if all its angles are
7 min read
Trapezium: Types | Formulas |Properties & Examples
A Trapezium or Trapezoid is a quadrilateral (shape with 4 sides) with exactly one pair of opposite sides parallel to each other. The term "trapezium" comes from the Greek word "trapeze," meaning "table." It is a two-dimensional shape with four sides and four vertices. In the figure below, a and b ar
8 min read
Square in Maths - Area, Perimeter, Examples & Applications
A square is a type of quadrilateral where all four sides are of equal length and each interior angle measures 90°. It has two pairs of parallel sides, with opposite sides being parallel. The diagonals of a square are equal in length and bisect each other at right angles.Squares are used in various f
5 min read
Kite - Quadrilaterals
A Kite is a special type of quadrilateral that is easily recognizable by its unique shape, resembling the traditional toy flown on a string. In geometry, a kite has two pairs of adjacent sides that are of equal length. This distinctive feature sets it apart from other quadrilaterals like squares, re
8 min read
Properties of Parallelograms
Properties of Parallelograms: Parallelogram is a quadrilateral in which opposite sides are parallel and congruent and the opposite angles are equal. A parallelogram is formed by the intersection of two pairs of parallel lines. In this article, we will learn about the properties of parallelograms, in
9 min read
Mid Point Theorem
The Midpoint Theorem is a fundamental concept in geometry that simplifies solving problems involving triangles. It establishes a relationship between the midpoints of two sides of a triangle and the third side. This theorem is especially useful in coordinate geometry and in proving other mathematica
6 min read
Chapter 9: Areas of Parallelograms and Triangles