Solve for x
x = \frac{30}{7} = 4\frac{2}{7} \approx 4.285714286
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30-3x-4x=0
Subtract 4x from both sides.
30-7x=0
Combine -3x and -4x to get -7x.
-7x=-30
Subtract 30 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-30}{-7}
Divide both sides by -7.
x=\frac{30}{7}
Fraction \frac{-30}{-7} can be simplified to \frac{30}{7} by removing the negative sign from both the numerator and the denominator.
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