Question

x-z=7
x+y=3
z-y=6
x= ?

Answer 1

subtract eq. 1 & 2

Answer 2

u will get a eq in y and z
then solve simultaneously with z-y=6

Answer 3

but when i try to solve the new eq. with the 3rd one it gives me -y+-y=10 which will cancel the y's out right?