(1) 5x + 2y = 11
(2) 4x - 3y = 18
Multiply (1) by 4
Multiply (2) by 5
This gives equation (3) and (4)
(3) 20x + 8y = 44
(4) 20x - 15y = 90
(3) - (4)
23y = -46
-46
y = -------- = -2
23
Substitute y into equation (2)
4x - 3(-2) = 18
4x + 6 = 18
4x = 12
x = 3