Solve for x
x=-\frac{4}{5}=-0.8
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40\left(5+x\right)=\left(x+12\right)\times 15
Variable x cannot be equal to -12 since division by zero is not defined. Multiply both sides of the equation by 40\left(x+12\right), the least common multiple of 12+x,40.
200+40x=\left(x+12\right)\times 15
Use the distributive property to multiply 40 by 5+x.
200+40x=15x+180
Use the distributive property to multiply x+12 by 15.
200+40x-15x=180
Subtract 15x from both sides.
200+25x=180
Combine 40x and -15x to get 25x.
25x=180-200
Subtract 200 from both sides.
25x=-20
Subtract 200 from 180 to get -20.
x=\frac{-20}{25}
Divide both sides by 25.
x=-\frac{4}{5}
Reduce the fraction \frac{-20}{25} to lowest terms by extracting and canceling out 5.
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