Solve for x
x = \frac{3 \sqrt{14}}{2} \approx 5.61248608
x = -\frac{3 \sqrt{14}}{2} \approx -5.61248608
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3x^{2}+44-7x^{2}=-82
Subtract 7x^{2} from both sides.
-4x^{2}+44=-82
Combine 3x^{2} and -7x^{2} to get -4x^{2}.
-4x^{2}=-82-44
Subtract 44 from both sides.
-4x^{2}=-126
Subtract 44 from -82 to get -126.
x^{2}=\frac{-126}{-4}
Divide both sides by -4.
x^{2}=\frac{63}{2}
Reduce the fraction \frac{-126}{-4} to lowest terms by extracting and canceling out -2.
x=\frac{3\sqrt{14}}{2} x=-\frac{3\sqrt{14}}{2}
Take the square root of both sides of the equation.
3x^{2}+44-7x^{2}=-82
Subtract 7x^{2} from both sides.
-4x^{2}+44=-82
Combine 3x^{2} and -7x^{2} to get -4x^{2}.
-4x^{2}+44+82=0
Add 82 to both sides.
-4x^{2}+126=0
Add 44 and 82 to get 126.
x=\frac{0±\sqrt{0^{2}-4\left(-4\right)\times 126}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, 0 for b, and 126 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-4\right)\times 126}}{2\left(-4\right)}
Square 0.
x=\frac{0±\sqrt{16\times 126}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{0±\sqrt{2016}}{2\left(-4\right)}
Multiply 16 times 126.
x=\frac{0±12\sqrt{14}}{2\left(-4\right)}
Take the square root of 2016.
x=\frac{0±12\sqrt{14}}{-8}
Multiply 2 times -4.
x=-\frac{3\sqrt{14}}{2}
Now solve the equation x=\frac{0±12\sqrt{14}}{-8} when ± is plus.
x=\frac{3\sqrt{14}}{2}
Now solve the equation x=\frac{0±12\sqrt{14}}{-8} when ± is minus.
x=-\frac{3\sqrt{14}}{2} x=\frac{3\sqrt{14}}{2}
The equation is now solved.
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