# Linear Equations :How do you solve the linear quadratic equations? : Class 9 Mathematics

Linear Equations : How do you solve the linear quadratic equations? : Class 9 Mathematics

In this video, we are going to study the topic named as, Linear Equations from class 9 Mathematics.

What are Linear Equations in Two Variables?
Each linear equation in two variables can be defined in a straight line. To solve a system of two linear equations in two variables, we graph both equations in the same coordinate system.

The equation that can be represented in the form of px + qy + r = 0 is called a two variable linear equation.

Key Points
There are infinitely many solutions possible for a linear equation in 2 variables. The graph of such equations is always a straight line.
In a two variable linear equation, x = 0 denotes the equation of y-axis and y = 0 denotes the equation of the x-axis. The graph of equation x = c represents a straight line parallel to the y-axis.

Similarly, the graph of equation y = c represents a straight line parallel to the x-axis. The equation y = cx (where c = constant) represents a line passing through the center (origin).
All the points on the graph of a 2 variable linear equation is a solution of the linear equation. The graph of a linear equation represents the solution of a linear equation.

All the above-mentioned topics are described in an interactive and efficient manner so that the students could easily understand them.