Solve for x
x=1
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21=21x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
21x=21
Swap sides so that all variable terms are on the left hand side.
x=\frac{21}{21}
Divide both sides by 21.
x=1
Divide 21 by 21 to get 1.
Examples
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Matrix
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Simultaneous equation
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Integration
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Limits
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