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1+2a^{2}-25a+34=0\times 0
Combine a^{2} and a^{2} to get 2a^{2}.
35+2a^{2}-25a=0\times 0
Add 1 and 34 to get 35.
35+2a^{2}-25a=0
Multiply 0 and 0 to get 0.
2a^{2}-25a+35=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.
a=\frac{-\left(-25\right)±\sqrt{\left(-25\right)^{2}-4\times 2\times 35}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -25 for b, and 35 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{-\left(-25\right)±\sqrt{625-4\times 2\times 35}}{2\times 2}
Square -25.
a=\frac{-\left(-25\right)±\sqrt{625-8\times 35}}{2\times 2}
Multiply -4 times 2.
a=\frac{-\left(-25\right)±\sqrt{625-280}}{2\times 2}
Multiply -8 times 35.
a=\frac{-\left(-25\right)±\sqrt{345}}{2\times 2}
Add 625 to -280.
a=\frac{25±\sqrt{345}}{2\times 2}
The opposite of -25 is 25.
a=\frac{25±\sqrt{345}}{4}
Multiply 2 times 2.
a=\frac{\sqrt{345}+25}{4}
Now solve the equation a=\frac{25±\sqrt{345}}{4} when ± is plus. Add 25 to \sqrt{345}.
a=\frac{25-\sqrt{345}}{4}
Now solve the equation a=\frac{25±\sqrt{345}}{4} when ± is minus. Subtract \sqrt{345} from 25.
a=\frac{\sqrt{345}+25}{4} a=\frac{25-\sqrt{345}}{4}
The equation is now solved.
1+2a^{2}-25a+34=0\times 0
Combine a^{2} and a^{2} to get 2a^{2}.
35+2a^{2}-25a=0\times 0
Add 1 and 34 to get 35.
35+2a^{2}-25a=0
Multiply 0 and 0 to get 0.
2a^{2}-25a=-35
Subtract 35 from both sides. Anything subtracted from zero gives its negation.
\frac{2a^{2}-25a}{2}=-\frac{35}{2}
Divide both sides by 2.
a^{2}-\frac{25}{2}a=-\frac{35}{2}
Dividing by 2 undoes the multiplication by 2.
a^{2}-\frac{25}{2}a+\left(-\frac{25}{4}\right)^{2}=-\frac{35}{2}+\left(-\frac{25}{4}\right)^{2}
Divide -\frac{25}{2}, the coefficient of the x term, by 2 to get -\frac{25}{4}. Then add the square of -\frac{25}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
a^{2}-\frac{25}{2}a+\frac{625}{16}=-\frac{35}{2}+\frac{625}{16}
Square -\frac{25}{4} by squaring both the numerator and the denominator of the fraction.
a^{2}-\frac{25}{2}a+\frac{625}{16}=\frac{345}{16}
Add -\frac{35}{2} to \frac{625}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(a-\frac{25}{4}\right)^{2}=\frac{345}{16}
Factor a^{2}-\frac{25}{2}a+\frac{625}{16}. 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{25}{4}\right)^{2}}=\sqrt{\frac{345}{16}}
Take the square root of both sides of the equation.
a-\frac{25}{4}=\frac{\sqrt{345}}{4} a-\frac{25}{4}=-\frac{\sqrt{345}}{4}
Simplify.
a=\frac{\sqrt{345}+25}{4} a=\frac{25-\sqrt{345}}{4}
Add \frac{25}{4} to both sides of the equation.