Solve for x
x = -\frac{225}{43} = -5\frac{10}{43} \approx -5.23255814
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90+18x=0.8x
Use the distributive property to multiply 5+x by 18.
90+18x-0.8x=0
Subtract 0.8x from both sides.
90+17.2x=0
Combine 18x and -0.8x to get 17.2x.
17.2x=-90
Subtract 90 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-90}{17.2}
Divide both sides by 17.2.
x=\frac{-900}{172}
Expand \frac{-90}{17.2} by multiplying both numerator and the denominator by 10.
x=-\frac{225}{43}
Reduce the fraction \frac{-900}{172} to lowest terms by extracting and canceling out 4.
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