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5x^{2}-107x+572=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{-\left(-107\right)±\sqrt{\left(-107\right)^{2}-4\times 5\times 572}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, -107 for b, and 572 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-107\right)±\sqrt{11449-4\times 5\times 572}}{2\times 5}
Square -107.
x=\frac{-\left(-107\right)±\sqrt{11449-20\times 572}}{2\times 5}
Multiply -4 times 5.
x=\frac{-\left(-107\right)±\sqrt{11449-11440}}{2\times 5}
Multiply -20 times 572.
x=\frac{-\left(-107\right)±\sqrt{9}}{2\times 5}
Add 11449 to -11440.
x=\frac{-\left(-107\right)±3}{2\times 5}
Take the square root of 9.
x=\frac{107±3}{2\times 5}
The opposite of -107 is 107.
x=\frac{107±3}{10}
Multiply 2 times 5.
x=\frac{110}{10}
Now solve the equation x=\frac{107±3}{10} when ± is plus. Add 107 to 3.
x=11
Divide 110 by 10.
x=\frac{104}{10}
Now solve the equation x=\frac{107±3}{10} when ± is minus. Subtract 3 from 107.
x=\frac{52}{5}
Reduce the fraction \frac{104}{10} to lowest terms by extracting and canceling out 2.
x=11 x=\frac{52}{5}
The equation is now solved.
5x^{2}-107x+572=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.
5x^{2}-107x+572-572=-572
Subtract 572 from both sides of the equation.
5x^{2}-107x=-572
Subtracting 572 from itself leaves 0.
\frac{5x^{2}-107x}{5}=-\frac{572}{5}
Divide both sides by 5.
x^{2}-\frac{107}{5}x=-\frac{572}{5}
Dividing by 5 undoes the multiplication by 5.
x^{2}-\frac{107}{5}x+\left(-\frac{107}{10}\right)^{2}=-\frac{572}{5}+\left(-\frac{107}{10}\right)^{2}
Divide -\frac{107}{5}, the coefficient of the x term, by 2 to get -\frac{107}{10}. Then add the square of -\frac{107}{10} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{107}{5}x+\frac{11449}{100}=-\frac{572}{5}+\frac{11449}{100}
Square -\frac{107}{10} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{107}{5}x+\frac{11449}{100}=\frac{9}{100}
Add -\frac{572}{5} to \frac{11449}{100} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{107}{10}\right)^{2}=\frac{9}{100}
Factor x^{2}-\frac{107}{5}x+\frac{11449}{100}. 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{107}{10}\right)^{2}}=\sqrt{\frac{9}{100}}
Take the square root of both sides of the equation.
x-\frac{107}{10}=\frac{3}{10} x-\frac{107}{10}=-\frac{3}{10}
Simplify.
x=11 x=\frac{52}{5}
Add \frac{107}{10} to both sides of the equation.