Question 114983
Since you do not give any directions of how the teacher wants it solved, I will go ahead and solve it by substitution;
x=3y+7
x+y=-5
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Since we already have one of the equations solved for x, lets substitute x in the other equation with that;
(3y+7)+y=-5
4y+7=-5
4y=-12
y=-3
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now we have what y =, so we can use that in either equation and solve for x;
x=3(-3)+7
x=-9+7
x=-2
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Let me know if you need it solved another way
:)