Answer:
First multiply the first equation by 2
2(2x + y = 25)
You'll have
4x + 2y = 50
Rewrite both equations
4x + 2y = 50
3x - 2y= 20
Add from the first equation you'll get
7x = 70... X = 10
Substitute x in one of the equations:
3(10) - 2y = 20
30 - 2y = 20
-2y = -10
y = 5