Question 566323
substitute what you have for y into your original problem of 4x-2y= 4. if y is 2x-2 then your new problem is now {{{ 4x-2(2x-2)= 4 }}} 

4x-2(2x-2)= 4
4x-4x+4= 4 *distributive property
0+4= 4
4= 4