Question

Solve the following equations graphically :
x+ 2y - 7 = 0
2x - y - 4 = 0

Answer 1

x+ 2y - 7 = 0........(1)
2x - y - 4 = 0.......(2)

x+ 2y - 7 = 0
⇒ x = 7 - 2y
Corresponding values of x and y can be tabulated as :

x	7	3	1
y	0	2	3

Plotting points (7, 0), (3, 2), (1, 3) and joining them, we get a line l₁ which is the graph of equation (1).

2x - y - 4
⇒  y = 2x - 4
Corresponding values of x and y can be tabulated as :

x	0	3	2
y	-4	2	0

Plotting points (0, -4), (3, 2), (2, 0) and joining them, we get a line l₂ which is the graph of equation (2).

The lines l₁ and l₂ intersect at a unique point (3, 2).