Solve for x
x=-5
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31=x-3x+21
Use the distributive property to multiply -3 by x-7.
31=-2x+21
Combine x and -3x to get -2x.
-2x+21=31
Swap sides so that all variable terms are on the left hand side.
-2x=31-21
Subtract 21 from both sides.
-2x=10
Subtract 21 from 31 to get 10.
x=\frac{10}{-2}
Divide both sides by -2.
x=-5
Divide 10 by -2 to get -5.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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