Solve for x
x=7
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21+x\times 8=11x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
21+x\times 8-11x=0
Subtract 11x from both sides.
21-3x=0
Combine x\times 8 and -11x to get -3x.
-3x=-21
Subtract 21 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-21}{-3}
Divide both sides by -3.
x=7
Divide -21 by -3 to get 7.
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