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x^{2}-9x+14=0
Use the distributive property to multiply x by x-9.
a+b=-9 ab=14
To solve the equation, factor x^{2}-9x+14 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,-14 -2,-7
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 14.
-1-14=-15 -2-7=-9
Calculate the sum for each pair.
a=-7 b=-2
The solution is the pair that gives sum -9.
\left(x-7\right)\left(x-2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=7 x=2
To find equation solutions, solve x-7=0 and x-2=0.
x^{2}-9x+14=0
Use the distributive property to multiply x by x-9.
a+b=-9 ab=1\times 14=14
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+14. To find a and b, set up a system to be solved.
-1,-14 -2,-7
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 14.
-1-14=-15 -2-7=-9
Calculate the sum for each pair.
a=-7 b=-2
The solution is the pair that gives sum -9.
\left(x^{2}-7x\right)+\left(-2x+14\right)
Rewrite x^{2}-9x+14 as \left(x^{2}-7x\right)+\left(-2x+14\right).
x\left(x-7\right)-2\left(x-7\right)
Factor out x in the first and -2 in the second group.
\left(x-7\right)\left(x-2\right)
Factor out common term x-7 by using distributive property.
x=7 x=2
To find equation solutions, solve x-7=0 and x-2=0.
x^{2}-9x+14=0
Use the distributive property to multiply x by x-9.
x=\frac{-\left(-9\right)±\sqrt{\left(-9\right)^{2}-4\times 14}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -9 for b, and 14 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-9\right)±\sqrt{81-4\times 14}}{2}
Square -9.
x=\frac{-\left(-9\right)±\sqrt{81-56}}{2}
Multiply -4 times 14.
x=\frac{-\left(-9\right)±\sqrt{25}}{2}
Add 81 to -56.
x=\frac{-\left(-9\right)±5}{2}
Take the square root of 25.
x=\frac{9±5}{2}
The opposite of -9 is 9.
x=\frac{14}{2}
Now solve the equation x=\frac{9±5}{2} when ± is plus. Add 9 to 5.
x=7
Divide 14 by 2.
x=\frac{4}{2}
Now solve the equation x=\frac{9±5}{2} when ± is minus. Subtract 5 from 9.
x=2
Divide 4 by 2.
x=7 x=2
The equation is now solved.
x^{2}-9x+14=0
Use the distributive property to multiply x by x-9.
x^{2}-9x=-14
Subtract 14 from both sides. Anything subtracted from zero gives its negation.
x^{2}-9x+\left(-\frac{9}{2}\right)^{2}=-14+\left(-\frac{9}{2}\right)^{2}
Divide -9, the coefficient of the x term, by 2 to get -\frac{9}{2}. Then add the square of -\frac{9}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-9x+\frac{81}{4}=-14+\frac{81}{4}
Square -\frac{9}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-9x+\frac{81}{4}=\frac{25}{4}
Add -14 to \frac{81}{4}.
\left(x-\frac{9}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}-9x+\frac{81}{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{9}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x-\frac{9}{2}=\frac{5}{2} x-\frac{9}{2}=-\frac{5}{2}
Simplify.
x=7 x=2
Add \frac{9}{2} to both sides of the equation.