Solve for x
x = -\frac{44}{7} = -6\frac{2}{7} \approx -6.285714286
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\left(x+5\right)\times 4x-\left(x-4\right)\times 2=4\left(x-4\right)\left(x+5\right)
Variable x cannot be equal to any of the values -5,4 since division by zero is not defined. Multiply both sides of the equation by \left(x-4\right)\left(x+5\right), the least common multiple of x-4,x+5.
\left(4x+20\right)x-\left(x-4\right)\times 2=4\left(x-4\right)\left(x+5\right)
Use the distributive property to multiply x+5 by 4.
4x^{2}+20x-\left(x-4\right)\times 2=4\left(x-4\right)\left(x+5\right)
Use the distributive property to multiply 4x+20 by x.
4x^{2}+20x-\left(2x-8\right)=4\left(x-4\right)\left(x+5\right)
Use the distributive property to multiply x-4 by 2.
4x^{2}+20x-2x+8=4\left(x-4\right)\left(x+5\right)
To find the opposite of 2x-8, find the opposite of each term.
4x^{2}+18x+8=4\left(x-4\right)\left(x+5\right)
Combine 20x and -2x to get 18x.
4x^{2}+18x+8=\left(4x-16\right)\left(x+5\right)
Use the distributive property to multiply 4 by x-4.
4x^{2}+18x+8=4x^{2}+4x-80
Use the distributive property to multiply 4x-16 by x+5 and combine like terms.
4x^{2}+18x+8-4x^{2}=4x-80
Subtract 4x^{2} from both sides.
18x+8=4x-80
Combine 4x^{2} and -4x^{2} to get 0.
18x+8-4x=-80
Subtract 4x from both sides.
14x+8=-80
Combine 18x and -4x to get 14x.
14x=-80-8
Subtract 8 from both sides.
14x=-88
Subtract 8 from -80 to get -88.
x=\frac{-88}{14}
Divide both sides by 14.
x=-\frac{44}{7}
Reduce the fraction \frac{-88}{14} to lowest terms by extracting and canceling out 2.
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Limits
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