Question

-x + 5y = 20

12y = 2x + 60

Answer 1

-x+5y=20
5y=x+20
12y=2x+60
6y=x+40
x+20+y=x+40
-x from each side:
20+y=40
-20 from each side:
y=20

-x+5*20=20
-x+100=20
-100 from each side:
-x=-80
x=80

y=20
x=80

Hope this helps :)