Solve for both systems 5x+7z=14 and 12x+2z=4

12x+2z=4

12x-12x+2z=4-12x

2z=4-12x

2z/2=4-12x/2

z=2-6x

5x+7z=14

5x+7(2-6x)=14

5x+7(2) (7)(-6x)=14

5x+14-42x=14

14-37x=14

14-37x-14=14-14

-37x=0

-37x/-37=0/-37

x=0

z=2-6x

z=2-6(0)

z=2-2=2