9514 1404 393
Answer:
x = -4
Explanation:
Start by eliminating parentheses and collecting terms.
2x +8x +28 = 6x +12 . . . . eliminate parentheses
10x +28 = 6x +12 . . . . . . . collect terms
4x +28 = 12 . . . . . . . . . . subtract 6x
4x = -16 . . . . . . . . . . . .subtract 28
x = -4 . . . . . . . . . . . divide by 4
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Check
2(-4) +4(2(-4) +7) = 3(2(-4) +4) . . . . substitute for x
-8 +4(-8 +7) = 3(-8 +4) . . . . evaluate products in parentheses
-8 +4(-1) = 3(-4) . . . . . . evaluate sums in parentheses
-8 -4 = -12 . . . . . . . . . true