Solve for x
x=\frac{5}{7}\approx 0.714285714
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21x=5\times 3
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 5x, the least common multiple of 5,x.
21x=15
Multiply 5 and 3 to get 15.
x=\frac{15}{21}
Divide both sides by 21.
x=\frac{5}{7}
Reduce the fraction \frac{15}{21} to lowest terms by extracting and canceling out 3.
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