How to Graph a Linear Equation using Excel?

Last Updated : 10 Jun, 2022

The equation having the highest degree is 1 is known as a linear equation. If we plot the graph for a linear equation, it always comes out to be a straight line. There are different forms of linear equations such as linear equations in one variable, and linear equations in two variables.

Linear equations in one variable: standard form of this equation is 'ax + b = 0', where a and b are real numbers and x is a variable.
Linear equation in two variables: standard form or this equation is, 'ax + by = c', where a, b and c are real numbers, and x is a variable.

Graph a linear equation using Excel

Graph of Linear equation (one variable)

In only one variable, the value of only one variable is needed to be found. Therefore, the equation can be solved directly. Let's take one linear equation in one variable i.e 2x + 3 = 9.

Step 1: Solve the linear equation

2x + 3 = 9

2x = 9 - 3

2x = 6

x = 6/2

x = 3

Step 2: Plot the graph

For a linear equation in one variable, the graph will always have a line parallel to any axis.

For x = 3, the graph will be a line parallel to the y-axis which intersects the x-axis at 3, because for any value of y, the value of x is 3. Below table data can be used to plot the graph,

Co-ordinates taken is (3, 0), (3, 5), (3, 10), (3, 15), (3, -5), (3, -10), (3, -15).

Plot the graph using the following steps

Step 1: Select the data

Step 2: Click on the 'Insert' tab and select scatter with marker chart.

Output

Graph of Linear equation (two variables)

Let's take one linear equation in one variable i.e 2x + 3y = 6. In order to get the data points for plotting the graph, assume some value of x and find the corresponding y value.

For example, If x = 0

Substitute value of x in given equation,

2(0) + 3y = 6

3y = 6

y = 2

Then, the data point is (0, 2). Similarly, we can get different coordinates, those are (3, 0), (-3, 4), and (6, -2).