Solve for x
x=-\frac{5}{7}\approx -0.714285714
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15+25x-4x=0
Subtract 4x from both sides.
15+21x=0
Combine 25x and -4x to get 21x.
21x=-15
Subtract 15 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-15}{21}
Divide both sides by 21.
x=-\frac{5}{7}
Reduce the fraction \frac{-15}{21} to lowest terms by extracting and canceling out 3.
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