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3x^{2}-1200x=0
Multiply 24 and 50 to get 1200.
x\left(3x-1200\right)=0
Factor out x.
x=0 x=400
To find equation solutions, solve x=0 and 3x-1200=0.
3x^{2}-1200x=0
Multiply 24 and 50 to get 1200.
x=\frac{-\left(-1200\right)±\sqrt{\left(-1200\right)^{2}}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -1200 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1200\right)±1200}{2\times 3}
Take the square root of \left(-1200\right)^{2}.
x=\frac{1200±1200}{2\times 3}
The opposite of -1200 is 1200.
x=\frac{1200±1200}{6}
Multiply 2 times 3.
x=\frac{2400}{6}
Now solve the equation x=\frac{1200±1200}{6} when ± is plus. Add 1200 to 1200.
x=400
Divide 2400 by 6.
x=\frac{0}{6}
Now solve the equation x=\frac{1200±1200}{6} when ± is minus. Subtract 1200 from 1200.
x=0
Divide 0 by 6.
x=400 x=0
The equation is now solved.
3x^{2}-1200x=0
Multiply 24 and 50 to get 1200.
\frac{3x^{2}-1200x}{3}=\frac{0}{3}
Divide both sides by 3.
x^{2}+\left(-\frac{1200}{3}\right)x=\frac{0}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}-400x=\frac{0}{3}
Divide -1200 by 3.
x^{2}-400x=0
Divide 0 by 3.
x^{2}-400x+\left(-200\right)^{2}=\left(-200\right)^{2}
Divide -400, the coefficient of the x term, by 2 to get -200. Then add the square of -200 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-400x+40000=40000
Square -200.
\left(x-200\right)^{2}=40000
Factor x^{2}-400x+40000. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-200\right)^{2}}=\sqrt{40000}
Take the square root of both sides of the equation.
x-200=200 x-200=-200
Simplify.
x=400 x=0
Add 200 to both sides of the equation.