Solve for x
x=15
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4x-40=20
Multiply 8 and 5 to get 40.
4x=20+40
Add 40 to both sides.
4x=60
Add 20 and 40 to get 60.
x=\frac{60}{4}
Divide both sides by 4.
x=15
Divide 60 by 4 to get 15.
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