Solve for x
x=6
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3\times 40=20x
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 x,3.
120=20x
Multiply 3 and 40 to get 120.
20x=120
Swap sides so that all variable terms are on the left hand side.
x=\frac{120}{20}
Divide both sides by 20.
x=6
Divide 120 by 20 to get 6.
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