Solve for x
x=30
x=-30
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3x^{2}\times 2\times 100+30\left(3x\times 2x-2000\right)=642000
Multiply x and x to get x^{2}.
3x^{2}\times 2\times 100+30\left(3x^{2}\times 2-2000\right)=642000
Multiply x and x to get x^{2}.
6x^{2}\times 100+30\left(3x^{2}\times 2-2000\right)=642000
Multiply 3 and 2 to get 6.
600x^{2}+30\left(3x^{2}\times 2-2000\right)=642000
Multiply 6 and 100 to get 600.
600x^{2}+30\left(6x^{2}-2000\right)=642000
Multiply 3 and 2 to get 6.
600x^{2}+180x^{2}-60000=642000
Use the distributive property to multiply 30 by 6x^{2}-2000.
780x^{2}-60000=642000
Combine 600x^{2} and 180x^{2} to get 780x^{2}.
780x^{2}=642000+60000
Add 60000 to both sides.
780x^{2}=702000
Add 642000 and 60000 to get 702000.
x^{2}=\frac{702000}{780}
Divide both sides by 780.
x^{2}=900
Divide 702000 by 780 to get 900.
x=30 x=-30
Take the square root of both sides of the equation.
3x^{2}\times 2\times 100+30\left(3x\times 2x-2000\right)=642000
Multiply x and x to get x^{2}.
3x^{2}\times 2\times 100+30\left(3x^{2}\times 2-2000\right)=642000
Multiply x and x to get x^{2}.
6x^{2}\times 100+30\left(3x^{2}\times 2-2000\right)=642000
Multiply 3 and 2 to get 6.
600x^{2}+30\left(3x^{2}\times 2-2000\right)=642000
Multiply 6 and 100 to get 600.
600x^{2}+30\left(6x^{2}-2000\right)=642000
Multiply 3 and 2 to get 6.
600x^{2}+180x^{2}-60000=642000
Use the distributive property to multiply 30 by 6x^{2}-2000.
780x^{2}-60000=642000
Combine 600x^{2} and 180x^{2} to get 780x^{2}.
780x^{2}-60000-642000=0
Subtract 642000 from both sides.
780x^{2}-702000=0
Subtract 642000 from -60000 to get -702000.
x=\frac{0±\sqrt{0^{2}-4\times 780\left(-702000\right)}}{2\times 780}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 780 for a, 0 for b, and -702000 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 780\left(-702000\right)}}{2\times 780}
Square 0.
x=\frac{0±\sqrt{-3120\left(-702000\right)}}{2\times 780}
Multiply -4 times 780.
x=\frac{0±\sqrt{2190240000}}{2\times 780}
Multiply -3120 times -702000.
x=\frac{0±46800}{2\times 780}
Take the square root of 2190240000.
x=\frac{0±46800}{1560}
Multiply 2 times 780.
x=30
Now solve the equation x=\frac{0±46800}{1560} when ± is plus. Divide 46800 by 1560.
x=-30
Now solve the equation x=\frac{0±46800}{1560} when ± is minus. Divide -46800 by 1560.
x=30 x=-30
The equation is now solved.
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