Solve for x
x=40
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12x+20=30x\times \frac{1}{4}+30x\times \frac{1}{6}
Multiply both sides of the equation by 60, the least common multiple of 5,3,2,4,6.
12x+20=\frac{30}{4}x+30x\times \frac{1}{6}
Multiply 30 and \frac{1}{4} to get \frac{30}{4}.
12x+20=\frac{15}{2}x+30x\times \frac{1}{6}
Reduce the fraction \frac{30}{4} to lowest terms by extracting and canceling out 2.
12x+20=\frac{15}{2}x+\frac{30}{6}x
Multiply 30 and \frac{1}{6} to get \frac{30}{6}.
12x+20=\frac{15}{2}x+5x
Divide 30 by 6 to get 5.
12x+20=\frac{25}{2}x
Combine \frac{15}{2}x and 5x to get \frac{25}{2}x.
12x+20-\frac{25}{2}x=0
Subtract \frac{25}{2}x from both sides.
-\frac{1}{2}x+20=0
Combine 12x and -\frac{25}{2}x to get -\frac{1}{2}x.
-\frac{1}{2}x=-20
Subtract 20 from both sides. Anything subtracted from zero gives its negation.
x=-20\left(-2\right)
Multiply both sides by -2, the reciprocal of -\frac{1}{2}.
x=40
Multiply -20 and -2 to get 40.
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Limits
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