Solve for x
x=12
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20-x=\frac{2}{5}\times 20
Multiply both sides by 20.
20-x=\frac{2\times 20}{5}
Express \frac{2}{5}\times 20 as a single fraction.
20-x=\frac{40}{5}
Multiply 2 and 20 to get 40.
20-x=8
Divide 40 by 5 to get 8.
-x=8-20
Subtract 20 from both sides.
-x=-12
Subtract 20 from 8 to get -12.
x=12
Multiply both sides by -1.
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