4x - 2y = 12
x + 2y = 8
(to cancel 2y, solve by adding)
4x - 2y = 12
+
x + 2y = 8
4x + x = 5x
-2y + 2y = 0
12 + 8 = 20
5x = 20
÷5
x = 4
Substitute x=4 to one of the equation:
x + 2y = 8
4 + 2y =8
-4
2y. = 4
÷2
y. = 2
Check:
4 + (2x2) does give you 8
Hope this helps!