Solve for x
x=13
x=14
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a+b=-27 ab=182
To solve the equation, factor x^{2}-27x+182 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,-182 -2,-91 -7,-26 -13,-14
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 182.
-1-182=-183 -2-91=-93 -7-26=-33 -13-14=-27
Calculate the sum for each pair.
a=-14 b=-13
The solution is the pair that gives sum -27.
\left(x-14\right)\left(x-13\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=14 x=13
To find equation solutions, solve x-14=0 and x-13=0.
a+b=-27 ab=1\times 182=182
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+182. To find a and b, set up a system to be solved.
-1,-182 -2,-91 -7,-26 -13,-14
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 182.
-1-182=-183 -2-91=-93 -7-26=-33 -13-14=-27
Calculate the sum for each pair.
a=-14 b=-13
The solution is the pair that gives sum -27.
\left(x^{2}-14x\right)+\left(-13x+182\right)
Rewrite x^{2}-27x+182 as \left(x^{2}-14x\right)+\left(-13x+182\right).
x\left(x-14\right)-13\left(x-14\right)
Factor out x in the first and -13 in the second group.
\left(x-14\right)\left(x-13\right)
Factor out common term x-14 by using distributive property.
x=14 x=13
To find equation solutions, solve x-14=0 and x-13=0.
x^{2}-27x+182=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(-27\right)±\sqrt{\left(-27\right)^{2}-4\times 182}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -27 for b, and 182 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-27\right)±\sqrt{729-4\times 182}}{2}
Square -27.
x=\frac{-\left(-27\right)±\sqrt{729-728}}{2}
Multiply -4 times 182.
x=\frac{-\left(-27\right)±\sqrt{1}}{2}
Add 729 to -728.
x=\frac{-\left(-27\right)±1}{2}
Take the square root of 1.
x=\frac{27±1}{2}
The opposite of -27 is 27.
x=\frac{28}{2}
Now solve the equation x=\frac{27±1}{2} when ± is plus. Add 27 to 1.
x=14
Divide 28 by 2.
x=\frac{26}{2}
Now solve the equation x=\frac{27±1}{2} when ± is minus. Subtract 1 from 27.
x=13
Divide 26 by 2.
x=14 x=13
The equation is now solved.
x^{2}-27x+182=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}-27x+182-182=-182
Subtract 182 from both sides of the equation.
x^{2}-27x=-182
Subtracting 182 from itself leaves 0.
x^{2}-27x+\left(-\frac{27}{2}\right)^{2}=-182+\left(-\frac{27}{2}\right)^{2}
Divide -27, the coefficient of the x term, by 2 to get -\frac{27}{2}. Then add the square of -\frac{27}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-27x+\frac{729}{4}=-182+\frac{729}{4}
Square -\frac{27}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-27x+\frac{729}{4}=\frac{1}{4}
Add -182 to \frac{729}{4}.
\left(x-\frac{27}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}-27x+\frac{729}{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{27}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x-\frac{27}{2}=\frac{1}{2} x-\frac{27}{2}=-\frac{1}{2}
Simplify.
x=14 x=13
Add \frac{27}{2} to both sides of the equation.
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Limits
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