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\left(x-1\right)x\times 2=4\left(2000-x\right)
Variable x cannot be equal to 1 since division by zero is not defined. Multiply both sides of the equation by 4\left(x-1\right), the least common multiple of 4,x-1.
\left(x^{2}-x\right)\times 2=4\left(2000-x\right)
Use the distributive property to multiply x-1 by x.
2x^{2}-2x=4\left(2000-x\right)
Use the distributive property to multiply x^{2}-x by 2.
2x^{2}-2x=8000-4x
Use the distributive property to multiply 4 by 2000-x.
2x^{2}-2x-8000=-4x
Subtract 8000 from both sides.
2x^{2}-2x-8000+4x=0
Add 4x to both sides.
2x^{2}+2x-8000=0
Combine -2x and 4x to get 2x.
x=\frac{-2±\sqrt{2^{2}-4\times 2\left(-8000\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 2 for b, and -8000 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-2±\sqrt{4-4\times 2\left(-8000\right)}}{2\times 2}
Square 2.
x=\frac{-2±\sqrt{4-8\left(-8000\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-2±\sqrt{4+64000}}{2\times 2}
Multiply -8 times -8000.
x=\frac{-2±\sqrt{64004}}{2\times 2}
Add 4 to 64000.
x=\frac{-2±2\sqrt{16001}}{2\times 2}
Take the square root of 64004.
x=\frac{-2±2\sqrt{16001}}{4}
Multiply 2 times 2.
x=\frac{2\sqrt{16001}-2}{4}
Now solve the equation x=\frac{-2±2\sqrt{16001}}{4} when ± is plus. Add -2 to 2\sqrt{16001}.
x=\frac{\sqrt{16001}-1}{2}
Divide -2+2\sqrt{16001} by 4.
x=\frac{-2\sqrt{16001}-2}{4}
Now solve the equation x=\frac{-2±2\sqrt{16001}}{4} when ± is minus. Subtract 2\sqrt{16001} from -2.
x=\frac{-\sqrt{16001}-1}{2}
Divide -2-2\sqrt{16001} by 4.
x=\frac{\sqrt{16001}-1}{2} x=\frac{-\sqrt{16001}-1}{2}
The equation is now solved.
\left(x-1\right)x\times 2=4\left(2000-x\right)
Variable x cannot be equal to 1 since division by zero is not defined. Multiply both sides of the equation by 4\left(x-1\right), the least common multiple of 4,x-1.
\left(x^{2}-x\right)\times 2=4\left(2000-x\right)
Use the distributive property to multiply x-1 by x.
2x^{2}-2x=4\left(2000-x\right)
Use the distributive property to multiply x^{2}-x by 2.
2x^{2}-2x=8000-4x
Use the distributive property to multiply 4 by 2000-x.
2x^{2}-2x+4x=8000
Add 4x to both sides.
2x^{2}+2x=8000
Combine -2x and 4x to get 2x.
\frac{2x^{2}+2x}{2}=\frac{8000}{2}
Divide both sides by 2.
x^{2}+\frac{2}{2}x=\frac{8000}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+x=\frac{8000}{2}
Divide 2 by 2.
x^{2}+x=4000
Divide 8000 by 2.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=4000+\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+x+\frac{1}{4}=4000+\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+x+\frac{1}{4}=\frac{16001}{4}
Add 4000 to \frac{1}{4}.
\left(x+\frac{1}{2}\right)^{2}=\frac{16001}{4}
Factor x^{2}+x+\frac{1}{4}. 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+\frac{1}{2}\right)^{2}}=\sqrt{\frac{16001}{4}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{\sqrt{16001}}{2} x+\frac{1}{2}=-\frac{\sqrt{16001}}{2}
Simplify.
x=\frac{\sqrt{16001}-1}{2} x=\frac{-\sqrt{16001}-1}{2}
Subtract \frac{1}{2} from both sides of the equation.