Solve for x
x = \frac{21}{5} = 4\frac{1}{5} = 4.2
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5x=3\times 7
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x, the least common multiple of 3,x.
5x=21
Multiply 3 and 7 to get 21.
x=\frac{21}{5}
Divide both sides by 5.
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