Solve for x
x = \frac{3}{2} = 1\frac{1}{2} = 1.5
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5\left(x+12\right)=3\left(x+21\right)
Variable x cannot be equal to -21 since division by zero is not defined. Multiply both sides of the equation by 5\left(x+21\right), the least common multiple of 21+x,5.
5x+60=3\left(x+21\right)
Use the distributive property to multiply 5 by x+12.
5x+60=3x+63
Use the distributive property to multiply 3 by x+21.
5x+60-3x=63
Subtract 3x from both sides.
2x+60=63
Combine 5x and -3x to get 2x.
2x=63-60
Subtract 60 from both sides.
2x=3
Subtract 60 from 63 to get 3.
x=\frac{3}{2}
Divide both sides by 2.
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