Solve for x
x=\frac{3}{7}\approx 0.428571429
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20x+30-90x=0
Subtract 90x from both sides.
-70x+30=0
Combine 20x and -90x to get -70x.
-70x=-30
Subtract 30 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-30}{-70}
Divide both sides by -70.
x=\frac{3}{7}
Reduce the fraction \frac{-30}{-70} to lowest terms by extracting and canceling out -10.
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