3. Pair of Linear equations in Two Variables

A pair of linear equations in two variables consists of two equations that involve the same variables, usually written in the form ax + by + c = 0. Each equation represents a straight line on a graph, and the solution of the pair of equations is the point where the two lines intersect, which satisfies both equations simultaneously.

 

In this chapter, students learn different methods to solve these equations, including the graphical method, substitution method, and elimination method. The lesson also explains the possible relationships between two lines: intersecting lines (one solution), parallel lines (no solution), and coincident lines (infinitely many solutions). Understanding these concepts helps students solve many real-life problems involving relationships between two quantities.