Solve for x
x = \frac{120}{7} = 17\frac{1}{7} \approx 17.142857143
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120-4x=3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 120x, the least common multiple of x,-30,40.
120-4x-3x=0
Subtract 3x from both sides.
120-7x=0
Combine -4x and -3x to get -7x.
-7x=-120
Subtract 120 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-120}{-7}
Divide both sides by -7.
x=\frac{120}{7}
Fraction \frac{-120}{-7} can be simplified to \frac{120}{7} by removing the negative sign from both the numerator and the denominator.
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