Solve for x
x=-18
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\left(x-9\right)\times 4-\left(x+9\right)\times 2=5x
Variable x cannot be equal to any of the values -9,9 since division by zero is not defined. Multiply both sides of the equation by \left(x-9\right)\left(x+9\right), the least common multiple of x+9,x-9,x^{2}-81.
4x-36-\left(x+9\right)\times 2=5x
Use the distributive property to multiply x-9 by 4.
4x-36-\left(2x+18\right)=5x
Use the distributive property to multiply x+9 by 2.
4x-36-2x-18=5x
To find the opposite of 2x+18, find the opposite of each term.
2x-36-18=5x
Combine 4x and -2x to get 2x.
2x-54=5x
Subtract 18 from -36 to get -54.
2x-54-5x=0
Subtract 5x from both sides.
-3x-54=0
Combine 2x and -5x to get -3x.
-3x=54
Add 54 to both sides. Anything plus zero gives itself.
x=\frac{54}{-3}
Divide both sides by -3.
x=-18
Divide 54 by -3 to get -18.
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Limits
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