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x\left(-2x+34+2\right)=0
Factor out x.
x=0 x=18
To find equation solutions, solve x=0 and -2x+36=0.
-2x^{2}+36x=0
Combine 34x and 2x to get 36x.
x=\frac{-36±\sqrt{36^{2}}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 36 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-36±36}{2\left(-2\right)}
Take the square root of 36^{2}.
x=\frac{-36±36}{-4}
Multiply 2 times -2.
x=\frac{0}{-4}
Now solve the equation x=\frac{-36±36}{-4} when ± is plus. Add -36 to 36.
x=0
Divide 0 by -4.
x=-\frac{72}{-4}
Now solve the equation x=\frac{-36±36}{-4} when ± is minus. Subtract 36 from -36.
x=18
Divide -72 by -4.
x=0 x=18
The equation is now solved.
-2x^{2}+36x=0
Combine 34x and 2x to get 36x.
\frac{-2x^{2}+36x}{-2}=\frac{0}{-2}
Divide both sides by -2.
x^{2}+\frac{36}{-2}x=\frac{0}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-18x=\frac{0}{-2}
Divide 36 by -2.
x^{2}-18x=0
Divide 0 by -2.
x^{2}-18x+\left(-9\right)^{2}=\left(-9\right)^{2}
Divide -18, the coefficient of the x term, by 2 to get -9. Then add the square of -9 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-18x+81=81
Square -9.
\left(x-9\right)^{2}=81
Factor x^{2}-18x+81. 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-9\right)^{2}}=\sqrt{81}
Take the square root of both sides of the equation.
x-9=9 x-9=-9
Simplify.
x=18 x=0
Add 9 to both sides of the equation.