Solve for x
x=20
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3x\times 4-3\times 40+3x\left(-\frac{4}{3}\right)=40
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x, the least common multiple of x,3,3x.
12x-3\times 40+3x\left(-\frac{4}{3}\right)=40
Multiply 3 and 4 to get 12.
12x-120+3x\left(-\frac{4}{3}\right)=40
Multiply -3 and 40 to get -120.
12x-120-4x=40
Multiply 3 and -\frac{4}{3} to get -4.
8x-120=40
Combine 12x and -4x to get 8x.
8x=40+120
Add 120 to both sides.
8x=160
Add 40 and 120 to get 160.
x=\frac{160}{8}
Divide both sides by 8.
x=20
Divide 160 by 8 to get 20.
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