Solve for x
x=21
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4x=7\times 12
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 7x, the least common multiple of 7,x.
4x=84
Multiply 7 and 12 to get 84.
x=\frac{84}{4}
Divide both sides by 4.
x=21
Divide 84 by 4 to get 21.
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