Solve for x
x=15
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3x+8-4x=-7
Subtract 4x from both sides.
-x+8=-7
Combine 3x and -4x to get -x.
-x=-7-8
Subtract 8 from both sides.
-x=-15
Subtract 8 from -7 to get -15.
x=15
Multiply both sides by -1.
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Limits
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