Answer:
x = -35/4, y= 7
Step-by-step explanation:
4x+9y=28
-4x-y=28
Add the equations together
4x+9y=28
-4x-y=28
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8y = 56
Divide by 8
8y/8 = 56/8
y = 7
Now we can find x
4x +9y = 28
4x +9(7) = 28
4x +63 = 28
Subtract 63 from each side
4x+63-63= 28-63
4x =-35
Divide each side by 4
4x/4 = -35/4
x = -35/4
