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2x^{2}+4\left(4x-6\right)=8x
Multiply both sides of the equation by 2.
2x^{2}+16x-24=8x
Use the distributive property to multiply 4 by 4x-6.
2x^{2}+16x-24-8x=0
Subtract 8x from both sides.
2x^{2}+8x-24=0
Combine 16x and -8x to get 8x.
x^{2}+4x-12=0
Divide both sides by 2.
a+b=4 ab=1\left(-12\right)=-12
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-12. To find a and b, set up a system to be solved.
-1,12 -2,6 -3,4
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -12.
-1+12=11 -2+6=4 -3+4=1
Calculate the sum for each pair.
a=-2 b=6
The solution is the pair that gives sum 4.
\left(x^{2}-2x\right)+\left(6x-12\right)
Rewrite x^{2}+4x-12 as \left(x^{2}-2x\right)+\left(6x-12\right).
x\left(x-2\right)+6\left(x-2\right)
Factor out x in the first and 6 in the second group.
\left(x-2\right)\left(x+6\right)
Factor out common term x-2 by using distributive property.
x=2 x=-6
To find equation solutions, solve x-2=0 and x+6=0.
2x^{2}+4\left(4x-6\right)=8x
Multiply both sides of the equation by 2.
2x^{2}+16x-24=8x
Use the distributive property to multiply 4 by 4x-6.
2x^{2}+16x-24-8x=0
Subtract 8x from both sides.
2x^{2}+8x-24=0
Combine 16x and -8x to get 8x.
x=\frac{-8±\sqrt{8^{2}-4\times 2\left(-24\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 8 for b, and -24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\times 2\left(-24\right)}}{2\times 2}
Square 8.
x=\frac{-8±\sqrt{64-8\left(-24\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-8±\sqrt{64+192}}{2\times 2}
Multiply -8 times -24.
x=\frac{-8±\sqrt{256}}{2\times 2}
Add 64 to 192.
x=\frac{-8±16}{2\times 2}
Take the square root of 256.
x=\frac{-8±16}{4}
Multiply 2 times 2.
x=\frac{8}{4}
Now solve the equation x=\frac{-8±16}{4} when ± is plus. Add -8 to 16.
x=2
Divide 8 by 4.
x=-\frac{24}{4}
Now solve the equation x=\frac{-8±16}{4} when ± is minus. Subtract 16 from -8.
x=-6
Divide -24 by 4.
x=2 x=-6
The equation is now solved.
2x^{2}+4\left(4x-6\right)=8x
Multiply both sides of the equation by 2.
2x^{2}+16x-24=8x
Use the distributive property to multiply 4 by 4x-6.
2x^{2}+16x-24-8x=0
Subtract 8x from both sides.
2x^{2}+8x-24=0
Combine 16x and -8x to get 8x.
2x^{2}+8x=24
Add 24 to both sides. Anything plus zero gives itself.
\frac{2x^{2}+8x}{2}=\frac{24}{2}
Divide both sides by 2.
x^{2}+\frac{8}{2}x=\frac{24}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+4x=\frac{24}{2}
Divide 8 by 2.
x^{2}+4x=12
Divide 24 by 2.
x^{2}+4x+2^{2}=12+2^{2}
Divide 4, the coefficient of the x term, by 2 to get 2. Then add the square of 2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+4x+4=12+4
Square 2.
x^{2}+4x+4=16
Add 12 to 4.
\left(x+2\right)^{2}=16
Factor x^{2}+4x+4. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x+2\right)^{2}}=\sqrt{16}
Take the square root of both sides of the equation.
x+2=4 x+2=-4
Simplify.
x=2 x=-6
Subtract 2 from both sides of the equation.