Solve for x
x=2
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21x-18=10x+2x
Combine 20x and x to get 21x.
21x-18=12x
Combine 10x and 2x to get 12x.
21x-18-12x=0
Subtract 12x from both sides.
9x-18=0
Combine 21x and -12x to get 9x.
9x=18
Add 18 to both sides. Anything plus zero gives itself.
x=\frac{18}{9}
Divide both sides by 9.
x=2
Divide 18 by 9 to get 2.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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