Solve for x
x = \frac{3 \sqrt{2990}}{13} \approx 12.61866749
x = -\frac{3 \sqrt{2990}}{13} \approx -12.61866749
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780x^{2}-60000=64200
Combine 600x^{2} and 180x^{2} to get 780x^{2}.
780x^{2}=64200+60000
Add 60000 to both sides.
780x^{2}=124200
Add 64200 and 60000 to get 124200.
x^{2}=\frac{124200}{780}
Divide both sides by 780.
x^{2}=\frac{2070}{13}
Reduce the fraction \frac{124200}{780} to lowest terms by extracting and canceling out 60.
x=\frac{3\sqrt{2990}}{13} x=-\frac{3\sqrt{2990}}{13}
Take the square root of both sides of the equation.
780x^{2}-60000=64200
Combine 600x^{2} and 180x^{2} to get 780x^{2}.
780x^{2}-60000-64200=0
Subtract 64200 from both sides.
780x^{2}-124200=0
Subtract 64200 from -60000 to get -124200.
x=\frac{0±\sqrt{0^{2}-4\times 780\left(-124200\right)}}{2\times 780}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 780 for a, 0 for b, and -124200 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 780\left(-124200\right)}}{2\times 780}
Square 0.
x=\frac{0±\sqrt{-3120\left(-124200\right)}}{2\times 780}
Multiply -4 times 780.
x=\frac{0±\sqrt{387504000}}{2\times 780}
Multiply -3120 times -124200.
x=\frac{0±360\sqrt{2990}}{2\times 780}
Take the square root of 387504000.
x=\frac{0±360\sqrt{2990}}{1560}
Multiply 2 times 780.
x=\frac{3\sqrt{2990}}{13}
Now solve the equation x=\frac{0±360\sqrt{2990}}{1560} when ± is plus.
x=-\frac{3\sqrt{2990}}{13}
Now solve the equation x=\frac{0±360\sqrt{2990}}{1560} when ± is minus.
x=\frac{3\sqrt{2990}}{13} x=-\frac{3\sqrt{2990}}{13}
The equation is now solved.
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