Solve for x (complex solution)
x=-\sqrt{7}i\approx -0-2.645751311i
x=\sqrt{7}i\approx 2.645751311i
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4x^{2}+2x+16=7x-12-5x
Combine -x and 3x to get 2x.
4x^{2}+2x+16=2x-12
Combine 7x and -5x to get 2x.
4x^{2}+2x+16-2x=-12
Subtract 2x from both sides.
4x^{2}+16=-12
Combine 2x and -2x to get 0.
4x^{2}=-12-16
Subtract 16 from both sides.
4x^{2}=-28
Subtract 16 from -12 to get -28.
x^{2}=\frac{-28}{4}
Divide both sides by 4.
x^{2}=-7
Divide -28 by 4 to get -7.
x=\sqrt{7}i x=-\sqrt{7}i
The equation is now solved.
4x^{2}+2x+16=7x-12-5x
Combine -x and 3x to get 2x.
4x^{2}+2x+16=2x-12
Combine 7x and -5x to get 2x.
4x^{2}+2x+16-2x=-12
Subtract 2x from both sides.
4x^{2}+16=-12
Combine 2x and -2x to get 0.
4x^{2}+16+12=0
Add 12 to both sides.
4x^{2}+28=0
Add 16 and 12 to get 28.
x=\frac{0±\sqrt{0^{2}-4\times 4\times 28}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, 0 for b, and 28 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 4\times 28}}{2\times 4}
Square 0.
x=\frac{0±\sqrt{-16\times 28}}{2\times 4}
Multiply -4 times 4.
x=\frac{0±\sqrt{-448}}{2\times 4}
Multiply -16 times 28.
x=\frac{0±8\sqrt{7}i}{2\times 4}
Take the square root of -448.
x=\frac{0±8\sqrt{7}i}{8}
Multiply 2 times 4.
x=\sqrt{7}i
Now solve the equation x=\frac{0±8\sqrt{7}i}{8} when ± is plus.
x=-\sqrt{7}i
Now solve the equation x=\frac{0±8\sqrt{7}i}{8} when ± is minus.
x=\sqrt{7}i x=-\sqrt{7}i
The equation is now solved.
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