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0=x\left(200+1500-10x\right)
Use the distributive property to multiply 10 by 150-x.
0=x\left(1700-10x\right)
Add 200 and 1500 to get 1700.
0=1700x-10x^{2}
Use the distributive property to multiply x by 1700-10x.
1700x-10x^{2}=0
Swap sides so that all variable terms are on the left hand side.
x\left(1700-10x\right)=0
Factor out x.
x=0 x=170
To find equation solutions, solve x=0 and 1700-10x=0.
0=x\left(200+1500-10x\right)
Use the distributive property to multiply 10 by 150-x.
0=x\left(1700-10x\right)
Add 200 and 1500 to get 1700.
0=1700x-10x^{2}
Use the distributive property to multiply x by 1700-10x.
1700x-10x^{2}=0
Swap sides so that all variable terms are on the left hand side.
-10x^{2}+1700x=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-1700±\sqrt{1700^{2}}}{2\left(-10\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -10 for a, 1700 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1700±1700}{2\left(-10\right)}
Take the square root of 1700^{2}.
x=\frac{-1700±1700}{-20}
Multiply 2 times -10.
x=\frac{0}{-20}
Now solve the equation x=\frac{-1700±1700}{-20} when ± is plus. Add -1700 to 1700.
x=0
Divide 0 by -20.
x=-\frac{3400}{-20}
Now solve the equation x=\frac{-1700±1700}{-20} when ± is minus. Subtract 1700 from -1700.
x=170
Divide -3400 by -20.
x=0 x=170
The equation is now solved.
0=x\left(200+1500-10x\right)
Use the distributive property to multiply 10 by 150-x.
0=x\left(1700-10x\right)
Add 200 and 1500 to get 1700.
0=1700x-10x^{2}
Use the distributive property to multiply x by 1700-10x.
1700x-10x^{2}=0
Swap sides so that all variable terms are on the left hand side.
-10x^{2}+1700x=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-10x^{2}+1700x}{-10}=\frac{0}{-10}
Divide both sides by -10.
x^{2}+\frac{1700}{-10}x=\frac{0}{-10}
Dividing by -10 undoes the multiplication by -10.
x^{2}-170x=\frac{0}{-10}
Divide 1700 by -10.
x^{2}-170x=0
Divide 0 by -10.
x^{2}-170x+\left(-85\right)^{2}=\left(-85\right)^{2}
Divide -170, the coefficient of the x term, by 2 to get -85. Then add the square of -85 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-170x+7225=7225
Square -85.
\left(x-85\right)^{2}=7225
Factor x^{2}-170x+7225. 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-85\right)^{2}}=\sqrt{7225}
Take the square root of both sides of the equation.
x-85=85 x-85=-85
Simplify.
x=170 x=0
Add 85 to both sides of the equation.