Solve for x
x=-2
x=2
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\left(x-4\right)\times 12-\left(4+x\right)\times 12=8\left(x-4\right)\left(x+4\right)
Variable x cannot be equal to any of the values -4,4 since division by zero is not defined. Multiply both sides of the equation by \left(x-4\right)\left(x+4\right), the least common multiple of 4+x,4-x.
12x-48-\left(4+x\right)\times 12=8\left(x-4\right)\left(x+4\right)
Use the distributive property to multiply x-4 by 12.
12x-48-12\left(4+x\right)=8\left(x-4\right)\left(x+4\right)
Multiply -1 and 12 to get -12.
12x-48-48-12x=8\left(x-4\right)\left(x+4\right)
Use the distributive property to multiply -12 by 4+x.
12x-96-12x=8\left(x-4\right)\left(x+4\right)
Subtract 48 from -48 to get -96.
-96=8\left(x-4\right)\left(x+4\right)
Combine 12x and -12x to get 0.
-96=\left(8x-32\right)\left(x+4\right)
Use the distributive property to multiply 8 by x-4.
-96=8x^{2}-128
Use the distributive property to multiply 8x-32 by x+4 and combine like terms.
8x^{2}-128=-96
Swap sides so that all variable terms are on the left hand side.
8x^{2}=-96+128
Add 128 to both sides.
8x^{2}=32
Add -96 and 128 to get 32.
x^{2}=\frac{32}{8}
Divide both sides by 8.
x^{2}=4
Divide 32 by 8 to get 4.
x=2 x=-2
Take the square root of both sides of the equation.
\left(x-4\right)\times 12-\left(4+x\right)\times 12=8\left(x-4\right)\left(x+4\right)
Variable x cannot be equal to any of the values -4,4 since division by zero is not defined. Multiply both sides of the equation by \left(x-4\right)\left(x+4\right), the least common multiple of 4+x,4-x.
12x-48-\left(4+x\right)\times 12=8\left(x-4\right)\left(x+4\right)
Use the distributive property to multiply x-4 by 12.
12x-48-12\left(4+x\right)=8\left(x-4\right)\left(x+4\right)
Multiply -1 and 12 to get -12.
12x-48-48-12x=8\left(x-4\right)\left(x+4\right)
Use the distributive property to multiply -12 by 4+x.
12x-96-12x=8\left(x-4\right)\left(x+4\right)
Subtract 48 from -48 to get -96.
-96=8\left(x-4\right)\left(x+4\right)
Combine 12x and -12x to get 0.
-96=\left(8x-32\right)\left(x+4\right)
Use the distributive property to multiply 8 by x-4.
-96=8x^{2}-128
Use the distributive property to multiply 8x-32 by x+4 and combine like terms.
8x^{2}-128=-96
Swap sides so that all variable terms are on the left hand side.
8x^{2}-128+96=0
Add 96 to both sides.
8x^{2}-32=0
Add -128 and 96 to get -32.
x=\frac{0±\sqrt{0^{2}-4\times 8\left(-32\right)}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 for a, 0 for b, and -32 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 8\left(-32\right)}}{2\times 8}
Square 0.
x=\frac{0±\sqrt{-32\left(-32\right)}}{2\times 8}
Multiply -4 times 8.
x=\frac{0±\sqrt{1024}}{2\times 8}
Multiply -32 times -32.
x=\frac{0±32}{2\times 8}
Take the square root of 1024.
x=\frac{0±32}{16}
Multiply 2 times 8.
x=2
Now solve the equation x=\frac{0±32}{16} when ± is plus. Divide 32 by 16.
x=-2
Now solve the equation x=\frac{0±32}{16} when ± is minus. Divide -32 by 16.
x=2 x=-2
The equation is now solved.
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