An equation of a straight lines is said to be linear equation. Linear equation is an equation between two variables which when plotted on a graph gives a straight line.

A general form a linear equation is:

*Ax + By + C = 0*

Where, **x** and **y** are the variables and A, B and C are
the constants. In a linear equation variables like x and y does not have
exponents.

For example: **y = 2x – 1**

x