Solve for x
x=21
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x\times 3=9\times 7
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 9x, the least common multiple of 9,x.
x\times 3=63
Multiply 9 and 7 to get 63.
x=\frac{63}{3}
Divide both sides by 3.
x=21
Divide 63 by 3 to get 21.
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