Question

x=2
2x-y=4
3x+2y-2z=4 solve by substitution

Answer 1

If x=2, put x into the second equation.
2(2)-y=4
4-y=4
-y=0
y=0.
Now you know y.
Plug x and y into the last equation.
3(2)+2(0)-2z=4
6+0-2z=4
-2z=-2
z=1.
x=2, y=0, z=1.

Answer 2

oh ok thanks...

Answer 3

Yep. :)