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\left(-a+2\right)a+\left(-a+2\right)\times 2-4=59\left(-a+2\right)
Variable a cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by -a+2.
-a^{2}+2a+\left(-a+2\right)\times 2-4=59\left(-a+2\right)
Use the distributive property to multiply -a+2 by a.
-a^{2}+2a-2a+4-4=59\left(-a+2\right)
Use the distributive property to multiply -a+2 by 2.
-a^{2}+4-4=59\left(-a+2\right)
Combine 2a and -2a to get 0.
-a^{2}=59\left(-a+2\right)
Subtract 4 from 4 to get 0.
-a^{2}=-59a+118
Use the distributive property to multiply 59 by -a+2.
-a^{2}+59a=118
Add 59a to both sides.
-a^{2}+59a-118=0
Subtract 118 from both sides.
a=\frac{-59±\sqrt{59^{2}-4\left(-1\right)\left(-118\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 59 for b, and -118 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{-59±\sqrt{3481-4\left(-1\right)\left(-118\right)}}{2\left(-1\right)}
Square 59.
a=\frac{-59±\sqrt{3481+4\left(-118\right)}}{2\left(-1\right)}
Multiply -4 times -1.
a=\frac{-59±\sqrt{3481-472}}{2\left(-1\right)}
Multiply 4 times -118.
a=\frac{-59±\sqrt{3009}}{2\left(-1\right)}
Add 3481 to -472.
a=\frac{-59±\sqrt{3009}}{-2}
Multiply 2 times -1.
a=\frac{\sqrt{3009}-59}{-2}
Now solve the equation a=\frac{-59±\sqrt{3009}}{-2} when ± is plus. Add -59 to \sqrt{3009}.
a=\frac{59-\sqrt{3009}}{2}
Divide -59+\sqrt{3009} by -2.
a=\frac{-\sqrt{3009}-59}{-2}
Now solve the equation a=\frac{-59±\sqrt{3009}}{-2} when ± is minus. Subtract \sqrt{3009} from -59.
a=\frac{\sqrt{3009}+59}{2}
Divide -59-\sqrt{3009} by -2.
a=\frac{59-\sqrt{3009}}{2} a=\frac{\sqrt{3009}+59}{2}
The equation is now solved.
\left(-a+2\right)a+\left(-a+2\right)\times 2-4=59\left(-a+2\right)
Variable a cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by -a+2.
-a^{2}+2a+\left(-a+2\right)\times 2-4=59\left(-a+2\right)
Use the distributive property to multiply -a+2 by a.
-a^{2}+2a-2a+4-4=59\left(-a+2\right)
Use the distributive property to multiply -a+2 by 2.
-a^{2}+4-4=59\left(-a+2\right)
Combine 2a and -2a to get 0.
-a^{2}=59\left(-a+2\right)
Subtract 4 from 4 to get 0.
-a^{2}=-59a+118
Use the distributive property to multiply 59 by -a+2.
-a^{2}+59a=118
Add 59a to both sides.
\frac{-a^{2}+59a}{-1}=\frac{118}{-1}
Divide both sides by -1.
a^{2}+\frac{59}{-1}a=\frac{118}{-1}
Dividing by -1 undoes the multiplication by -1.
a^{2}-59a=\frac{118}{-1}
Divide 59 by -1.
a^{2}-59a=-118
Divide 118 by -1.
a^{2}-59a+\left(-\frac{59}{2}\right)^{2}=-118+\left(-\frac{59}{2}\right)^{2}
Divide -59, the coefficient of the x term, by 2 to get -\frac{59}{2}. Then add the square of -\frac{59}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
a^{2}-59a+\frac{3481}{4}=-118+\frac{3481}{4}
Square -\frac{59}{2} by squaring both the numerator and the denominator of the fraction.
a^{2}-59a+\frac{3481}{4}=\frac{3009}{4}
Add -118 to \frac{3481}{4}.
\left(a-\frac{59}{2}\right)^{2}=\frac{3009}{4}
Factor a^{2}-59a+\frac{3481}{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(a-\frac{59}{2}\right)^{2}}=\sqrt{\frac{3009}{4}}
Take the square root of both sides of the equation.
a-\frac{59}{2}=\frac{\sqrt{3009}}{2} a-\frac{59}{2}=-\frac{\sqrt{3009}}{2}
Simplify.
a=\frac{\sqrt{3009}+59}{2} a=\frac{59-\sqrt{3009}}{2}
Add \frac{59}{2} to both sides of the equation.