wow, it can't get any easier
just add them:
5y = 20
y = 4
sub into the first:
x + 12 = 20
x = 8
x = 8, y = 4
solve using the elimination method.
x + 3y = 20
-x + 2y = 0
1 answer
x + 3y = 20
-x + 2y = 0
1 answer