Solve for x
x=7
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x=\frac{-21}{-3}
Divide both sides by -3.
x=7
Divide -21 by -3 to get 7.
Examples
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Matrix
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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