Solve for x
x=-16
x=-2
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x^{2}+18x+32=0
Swap sides so that all variable terms are on the left hand side.
a+b=18 ab=32
To solve the equation, factor x^{2}+18x+32 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.
1,32 2,16 4,8
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 32.
1+32=33 2+16=18 4+8=12
Calculate the sum for each pair.
a=2 b=16
The solution is the pair that gives sum 18.
\left(x+2\right)\left(x+16\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=-2 x=-16
To find equation solutions, solve x+2=0 and x+16=0.
x^{2}+18x+32=0
Swap sides so that all variable terms are on the left hand side.
a+b=18 ab=1\times 32=32
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+32. To find a and b, set up a system to be solved.
1,32 2,16 4,8
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 32.
1+32=33 2+16=18 4+8=12
Calculate the sum for each pair.
a=2 b=16
The solution is the pair that gives sum 18.
\left(x^{2}+2x\right)+\left(16x+32\right)
Rewrite x^{2}+18x+32 as \left(x^{2}+2x\right)+\left(16x+32\right).
x\left(x+2\right)+16\left(x+2\right)
Factor out x in the first and 16 in the second group.
\left(x+2\right)\left(x+16\right)
Factor out common term x+2 by using distributive property.
x=-2 x=-16
To find equation solutions, solve x+2=0 and x+16=0.
x^{2}+18x+32=0
Swap sides so that all variable terms are on the left hand side.
x=\frac{-18±\sqrt{18^{2}-4\times 32}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 18 for b, and 32 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-18±\sqrt{324-4\times 32}}{2}
Square 18.
x=\frac{-18±\sqrt{324-128}}{2}
Multiply -4 times 32.
x=\frac{-18±\sqrt{196}}{2}
Add 324 to -128.
x=\frac{-18±14}{2}
Take the square root of 196.
x=-\frac{4}{2}
Now solve the equation x=\frac{-18±14}{2} when ± is plus. Add -18 to 14.
x=-2
Divide -4 by 2.
x=-\frac{32}{2}
Now solve the equation x=\frac{-18±14}{2} when ± is minus. Subtract 14 from -18.
x=-16
Divide -32 by 2.
x=-2 x=-16
The equation is now solved.
x^{2}+18x+32=0
Swap sides so that all variable terms are on the left hand side.
x^{2}+18x=-32
Subtract 32 from both sides. Anything subtracted from zero gives its negation.
x^{2}+18x+9^{2}=-32+9^{2}
Divide 18, the coefficient of the x term, by 2 to get 9. Then add the square of 9 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+18x+81=-32+81
Square 9.
x^{2}+18x+81=49
Add -32 to 81.
\left(x+9\right)^{2}=49
Factor x^{2}+18x+81. 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+9\right)^{2}}=\sqrt{49}
Take the square root of both sides of the equation.
x+9=7 x+9=-7
Simplify.
x=-2 x=-16
Subtract 9 from both sides of the equation.
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Limits
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