Solve for x
x=2\sqrt{17}\approx 8.246211251
x=-2\sqrt{17}\approx -8.246211251
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\left(x+6\right)\left(x-6\right)=8\times 4
Variable x cannot be equal to -6 since division by zero is not defined. Multiply both sides of the equation by 8\left(x+6\right), the least common multiple of 8,x+6.
x^{2}-36=8\times 4
Consider \left(x+6\right)\left(x-6\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 6.
x^{2}-36=32
Multiply 8 and 4 to get 32.
x^{2}=32+36
Add 36 to both sides.
x^{2}=68
Add 32 and 36 to get 68.
x=2\sqrt{17} x=-2\sqrt{17}
Take the square root of both sides of the equation.
\left(x+6\right)\left(x-6\right)=8\times 4
Variable x cannot be equal to -6 since division by zero is not defined. Multiply both sides of the equation by 8\left(x+6\right), the least common multiple of 8,x+6.
x^{2}-36=8\times 4
Consider \left(x+6\right)\left(x-6\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 6.
x^{2}-36=32
Multiply 8 and 4 to get 32.
x^{2}-36-32=0
Subtract 32 from both sides.
x^{2}-68=0
Subtract 32 from -36 to get -68.
x=\frac{0±\sqrt{0^{2}-4\left(-68\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -68 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-68\right)}}{2}
Square 0.
x=\frac{0±\sqrt{272}}{2}
Multiply -4 times -68.
x=\frac{0±4\sqrt{17}}{2}
Take the square root of 272.
x=2\sqrt{17}
Now solve the equation x=\frac{0±4\sqrt{17}}{2} when ± is plus.
x=-2\sqrt{17}
Now solve the equation x=\frac{0±4\sqrt{17}}{2} when ± is minus.
x=2\sqrt{17} x=-2\sqrt{17}
The equation is now solved.
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