Solve for x
x=20
x=-20
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3x^{2}-1200=0
Multiply 24 and 50 to get 1200.
x^{2}-400=0
Divide both sides by 3.
\left(x-20\right)\left(x+20\right)=0
Consider x^{2}-400. Rewrite x^{2}-400 as x^{2}-20^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=20 x=-20
To find equation solutions, solve x-20=0 and x+20=0.
3x^{2}-1200=0
Multiply 24 and 50 to get 1200.
3x^{2}=1200
Add 1200 to both sides. Anything plus zero gives itself.
x^{2}=\frac{1200}{3}
Divide both sides by 3.
x^{2}=400
Divide 1200 by 3 to get 400.
x=20 x=-20
Take the square root of both sides of the equation.
3x^{2}-1200=0
Multiply 24 and 50 to get 1200.
x=\frac{0±\sqrt{0^{2}-4\times 3\left(-1200\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 0 for b, and -1200 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 3\left(-1200\right)}}{2\times 3}
Square 0.
x=\frac{0±\sqrt{-12\left(-1200\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{0±\sqrt{14400}}{2\times 3}
Multiply -12 times -1200.
x=\frac{0±120}{2\times 3}
Take the square root of 14400.
x=\frac{0±120}{6}
Multiply 2 times 3.
x=20
Now solve the equation x=\frac{0±120}{6} when ± is plus. Divide 120 by 6.
x=-20
Now solve the equation x=\frac{0±120}{6} when ± is minus. Divide -120 by 6.
x=20 x=-20
The equation is now solved.
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