WAEC - Mathematics (1997 - No. 8)

Solve the equations: 4x -y = 11; 5x + 2y = 4.

x = 6, y = 13

x = -2, y = -3

x = -2, y = 3

x = 2, y = -3

x = 2, y = 3.

4x - y = 11....(1) x 2 8x - 2y = 22....(3)

5x + 12y = 4....(2) x 1 5x + 2y = 4....(4)

add eqn (3) and (4)

13x = 26

x = 2

4(2) - y = 11 \(\implies\) y = 8 - 11

y = -3.