Solve for x
x=5
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7x-4-2x=21
Subtract 2x from both sides.
5x-4=21
Combine 7x and -2x to get 5x.
5x=21+4
Add 4 to both sides.
5x=25
Add 21 and 4 to get 25.
x=\frac{25}{5}
Divide both sides by 5.
x=5
Divide 25 by 5 to get 5.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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