Solve for x
x=4
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20-x=4x
Use the distributive property to multiply 20-x by 1.
20-x-4x=0
Subtract 4x from both sides.
20-5x=0
Combine -x and -4x to get -5x.
-5x=-20
Subtract 20 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-20}{-5}
Divide both sides by -5.
x=4
Divide -20 by -5 to get 4.
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