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x^{2}-37x+36.5=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(-37\right)±\sqrt{\left(-37\right)^{2}-4\times 36.5}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -37 for b, and 36.5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-37\right)±\sqrt{1369-4\times 36.5}}{2}
Square -37.
x=\frac{-\left(-37\right)±\sqrt{1369-146}}{2}
Multiply -4 times 36.5.
x=\frac{-\left(-37\right)±\sqrt{1223}}{2}
Add 1369 to -146.
x=\frac{37±\sqrt{1223}}{2}
The opposite of -37 is 37.
x=\frac{\sqrt{1223}+37}{2}
Now solve the equation x=\frac{37±\sqrt{1223}}{2} when ± is plus. Add 37 to \sqrt{1223}.
x=\frac{37-\sqrt{1223}}{2}
Now solve the equation x=\frac{37±\sqrt{1223}}{2} when ± is minus. Subtract \sqrt{1223} from 37.
x=\frac{\sqrt{1223}+37}{2} x=\frac{37-\sqrt{1223}}{2}
The equation is now solved.
x^{2}-37x+36.5=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.
x^{2}-37x+36.5-36.5=-36.5
Subtract 36.5 from both sides of the equation.
x^{2}-37x=-36.5
Subtracting 36.5 from itself leaves 0.
x^{2}-37x+\left(-\frac{37}{2}\right)^{2}=-36.5+\left(-\frac{37}{2}\right)^{2}
Divide -37, the coefficient of the x term, by 2 to get -\frac{37}{2}. Then add the square of -\frac{37}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-37x+\frac{1369}{4}=-36.5+\frac{1369}{4}
Square -\frac{37}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-37x+\frac{1369}{4}=\frac{1223}{4}
Add -36.5 to \frac{1369}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{37}{2}\right)^{2}=\frac{1223}{4}
Factor x^{2}-37x+\frac{1369}{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(x-\frac{37}{2}\right)^{2}}=\sqrt{\frac{1223}{4}}
Take the square root of both sides of the equation.
x-\frac{37}{2}=\frac{\sqrt{1223}}{2} x-\frac{37}{2}=-\frac{\sqrt{1223}}{2}
Simplify.
x=\frac{\sqrt{1223}+37}{2} x=\frac{37-\sqrt{1223}}{2}
Add \frac{37}{2} to both sides of the equation.