Solve for x
x=9
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3x-42-7x=-78
Subtract 7x from both sides.
-4x-42=-78
Combine 3x and -7x to get -4x.
-4x=-78+42
Add 42 to both sides.
-4x=-36
Add -78 and 42 to get -36.
x=\frac{-36}{-4}
Divide both sides by -4.
x=9
Divide -36 by -4 to get 9.
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