Solve for x
x = \frac{100}{21} = 4\frac{16}{21} \approx 4.761904762
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100-20x=x
Use the distributive property to multiply 20 by 5-x.
100-20x-x=0
Subtract x from both sides.
100-21x=0
Combine -20x and -x to get -21x.
-21x=-100
Subtract 100 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-100}{-21}
Divide both sides by -21.
x=\frac{100}{21}
Fraction \frac{-100}{-21} can be simplified to \frac{100}{21} by removing the negative sign from both the numerator and the denominator.
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