Question 120346
Substitution is the best method since the second equation has already been solved for y


Start with the given system

{{{2x-2y=-4}}}
{{{y=2}}}




{{{2x-2(2)=-4}}}  Plug in {{{y=2}}} into the first equation. In other words, replace each {{{y}}} with {{{2}}}. Notice we've eliminated the {{{y}}} variables. So we now have a simple equation with one unknown.



{{{2x-4=-4}}} Distribute



{{{2x=-4+4}}}Add 4 to both sides



{{{2x=0}}} Combine like terms on the right side



{{{x=(0)/(2)}}} Divide both sides by 2 to isolate x




{{{x=0}}} Divide



So our answer is {{{x=0}}} and {{{y=2}}} which also looks like (0,2)