Solve for x
x = -\frac{21}{8} = -2\frac{5}{8} = -2.625
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-8x-21=0
Combine 8x and -16x to get -8x.
-8x=21
Add 21 to both sides. Anything plus zero gives itself.
x=\frac{21}{-8}
Divide both sides by -8.
x=-\frac{21}{8}
Fraction \frac{21}{-8} can be rewritten as -\frac{21}{8} by extracting the negative sign.
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