2(x+y)=5dan4x-3y+18=0

2x + 2y = 5 (×2)
4x - 3y = -18 (×1)
-----------------------
4x + 4y = 10
4x - 3y = -18
----------------------- (-)
7y = 28
y = 28/7
y = 4

4x - 3y = -18
4x - 3(4) = -18
4x - 12 = -18
4x = -18 + 12
4x = -6
x = -6/4
x = -3/2

Maaf kalau salah peace