Solve for x
x=14
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2\left(21-x\right)=x
Multiply both sides of the equation by 12, the least common multiple of 6,12.
42-2x=x
Use the distributive property to multiply 2 by 21-x.
42-2x-x=0
Subtract x from both sides.
42-3x=0
Combine -2x and -x to get -3x.
-3x=-42
Subtract 42 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-42}{-3}
Divide both sides by -3.
x=14
Divide -42 by -3 to get 14.
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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