Solve for x
x=-14
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30=30\left(x+20\right)\times \frac{1}{15}+30\left(x+20\right)\times \frac{1}{10}
Variable x cannot be equal to -20 since division by zero is not defined. Multiply both sides of the equation by 30\left(x+20\right), the least common multiple of x+20,15,10.
30=2\left(x+20\right)+30\left(x+20\right)\times \frac{1}{10}
Multiply 30 and \frac{1}{15} to get 2.
30=2x+40+30\left(x+20\right)\times \frac{1}{10}
Use the distributive property to multiply 2 by x+20.
30=2x+40+3\left(x+20\right)
Multiply 30 and \frac{1}{10} to get 3.
30=2x+40+3x+60
Use the distributive property to multiply 3 by x+20.
30=5x+40+60
Combine 2x and 3x to get 5x.
30=5x+100
Add 40 and 60 to get 100.
5x+100=30
Swap sides so that all variable terms are on the left hand side.
5x=30-100
Subtract 100 from both sides.
5x=-70
Subtract 100 from 30 to get -70.
x=\frac{-70}{5}
Divide both sides by 5.
x=-14
Divide -70 by 5 to get -14.
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