Solve for x
x=5
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x\times \frac{21}{3.5}=30
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x\times \frac{210}{35}=30
Expand \frac{21}{3.5} by multiplying both numerator and the denominator by 10.
x\times 6=30
Divide 210 by 35 to get 6.
x=\frac{30}{6}
Divide both sides by 6.
x=5
Divide 30 by 6 to get 5.
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