Solve for x
x=20
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30x+900=75x
Combine 2x and -x to get x.
30x+900-75x=0
Subtract 75x from both sides.
-45x+900=0
Combine 30x and -75x to get -45x.
-45x=-900
Subtract 900 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-900}{-45}
Divide both sides by -45.
x=20
Divide -900 by -45 to get 20.
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