Solve for n
n=-6
n=6
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\left(2n+4\right)\left(n-2\right)=64
Use the distributive property to multiply 2 by n+2.
2n^{2}-8=64
Use the distributive property to multiply 2n+4 by n-2 and combine like terms.
2n^{2}=64+8
Add 8 to both sides.
2n^{2}=72
Add 64 and 8 to get 72.
n^{2}=\frac{72}{2}
Divide both sides by 2.
n^{2}=36
Divide 72 by 2 to get 36.
n=6 n=-6
Take the square root of both sides of the equation.
\left(2n+4\right)\left(n-2\right)=64
Use the distributive property to multiply 2 by n+2.
2n^{2}-8=64
Use the distributive property to multiply 2n+4 by n-2 and combine like terms.
2n^{2}-8-64=0
Subtract 64 from both sides.
2n^{2}-72=0
Subtract 64 from -8 to get -72.
n=\frac{0±\sqrt{0^{2}-4\times 2\left(-72\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -72 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
n=\frac{0±\sqrt{-4\times 2\left(-72\right)}}{2\times 2}
Square 0.
n=\frac{0±\sqrt{-8\left(-72\right)}}{2\times 2}
Multiply -4 times 2.
n=\frac{0±\sqrt{576}}{2\times 2}
Multiply -8 times -72.
n=\frac{0±24}{2\times 2}
Take the square root of 576.
n=\frac{0±24}{4}
Multiply 2 times 2.
n=6
Now solve the equation n=\frac{0±24}{4} when ± is plus. Divide 24 by 4.
n=-6
Now solve the equation n=\frac{0±24}{4} when ± is minus. Divide -24 by 4.
n=6 n=-6
The equation is now solved.
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