Y=x+4
3x+Y=-8
3x+x+4=-8
X=-3. Substitute the value of x
Y=-3+4
Y=1
(X,Y)= (-3,1)
So the answer is C
A) 2x + 10 equals 2x + 10
B) 7x + 3 does NOT equal 7x + 15
C) 4y - 8 doe NOT equal 4y - 2
D) 2y + 12 does NOT equal 2y - 12
Thus, A is the appropriate answer.
Hope that helped!
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