Question

Find the value of x- y  if 4x + 3y = 25, 3x + 4y = 24

Answer 1

4x + 3y = 25 .....(i)

3x + 4y = 24 .....(ii)

Equation (i) is multiply by 3 and (ii) by 4

∴ y = 3

∴ 4x + 3(3) = 25 

4x = 16

x = 4

∴ x - y = 4  -3 = 1