Solve for x
x=20
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90\times 2=x\times 9
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 90x, the least common multiple of x,90.
180=x\times 9
Multiply 90 and 2 to get 180.
x\times 9=180
Swap sides so that all variable terms are on the left hand side.
x=\frac{180}{9}
Divide both sides by 9.
x=20
Divide 180 by 9 to get 20.
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