Solve for x
x=-5
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3x-12-7x=8
Subtract 7x from both sides.
-4x-12=8
Combine 3x and -7x to get -4x.
-4x=8+12
Add 12 to both sides.
-4x=20
Add 8 and 12 to get 20.
x=\frac{20}{-4}
Divide both sides by -4.
x=-5
Divide 20 by -4 to get -5.
Examples
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Matrix
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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