Answer :
3x+4y=2
+ 4x-4y=12 add them since 4y and -4y can cancel out
7x=14 divide each side by 7
x=2
3x+4y=2 x=2
3(2)+4y=2 substitute
6+4y=2
-6 -6
4y=-4 divide each side by 4
y=-1
+ 4x-4y=12 add them since 4y and -4y can cancel out
7x=14 divide each side by 7
x=2
3x+4y=2 x=2
3(2)+4y=2 substitute
6+4y=2
-6 -6
4y=-4 divide each side by 4
y=-1