Solve for x y=7x-7z-9
A)x=y-7z-9/7
B)x=y+7z+9/7
C)x=y+z+9/7
D)x=y-z-9/7
A)x=y-7z-9/7
B)x=y+7z+9/7
C)x=y+z+9/7
D)x=y-z-9/7