x=2y+12 4x+4y=0 find x and y?

hi,your question :

x=2y+12

4x+4y=0

find x and y?

first let x=2y+12 be (1) and 4x+4y=0 be (2)

Sub (1) into (2), you will get the following equation:

4(2y+12) + 4y=0

then solve the equation:

8y+48+4y=0

12y+48=0

y=-4 

then sub y=-4 into (1) , you will get x=2(-4)+12,x=4

so y=-4 and x=4

hope I can help u :)