Solve for x
x=60
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0.3x+42-x=0
Subtract x from both sides.
-0.7x+42=0
Combine 0.3x and -x to get -0.7x.
-0.7x=-42
Subtract 42 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-42}{-0.7}
Divide both sides by -0.7.
x=\frac{-420}{-7}
Expand \frac{-42}{-0.7} by multiplying both numerator and the denominator by 10.
x=60
Divide -420 by -7 to get 60.
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