Solve for x
x = \frac{5}{2} = 2\frac{1}{2} = 2.5
x = -\frac{5}{2} = -2\frac{1}{2} = -2.5
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36x^{2}-100x^{2}+400=0
Use the distributive property to multiply -100 by x^{2}-4.
-64x^{2}+400=0
Combine 36x^{2} and -100x^{2} to get -64x^{2}.
-64x^{2}=-400
Subtract 400 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-400}{-64}
Divide both sides by -64.
x^{2}=\frac{25}{4}
Reduce the fraction \frac{-400}{-64} to lowest terms by extracting and canceling out -16.
x=\frac{5}{2} x=-\frac{5}{2}
Take the square root of both sides of the equation.
36x^{2}-100x^{2}+400=0
Use the distributive property to multiply -100 by x^{2}-4.
-64x^{2}+400=0
Combine 36x^{2} and -100x^{2} to get -64x^{2}.
x=\frac{0±\sqrt{0^{2}-4\left(-64\right)\times 400}}{2\left(-64\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -64 for a, 0 for b, and 400 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-64\right)\times 400}}{2\left(-64\right)}
Square 0.
x=\frac{0±\sqrt{256\times 400}}{2\left(-64\right)}
Multiply -4 times -64.
x=\frac{0±\sqrt{102400}}{2\left(-64\right)}
Multiply 256 times 400.
x=\frac{0±320}{2\left(-64\right)}
Take the square root of 102400.
x=\frac{0±320}{-128}
Multiply 2 times -64.
x=-\frac{5}{2}
Now solve the equation x=\frac{0±320}{-128} when ± is plus. Reduce the fraction \frac{320}{-128} to lowest terms by extracting and canceling out 64.
x=\frac{5}{2}
Now solve the equation x=\frac{0±320}{-128} when ± is minus. Reduce the fraction \frac{-320}{-128} to lowest terms by extracting and canceling out 64.
x=-\frac{5}{2} x=\frac{5}{2}
The equation is now solved.
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Limits
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