Solve for x
x=-30
x=6
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x^{2}+24x=180
Anything plus zero gives itself.
x^{2}+24x-180=0
Subtract 180 from both sides.
a+b=24 ab=-180
To solve the equation, factor x^{2}+24x-180 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.
-1,180 -2,90 -3,60 -4,45 -5,36 -6,30 -9,20 -10,18 -12,15
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -180.
-1+180=179 -2+90=88 -3+60=57 -4+45=41 -5+36=31 -6+30=24 -9+20=11 -10+18=8 -12+15=3
Calculate the sum for each pair.
a=-6 b=30
The solution is the pair that gives sum 24.
\left(x-6\right)\left(x+30\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=6 x=-30
To find equation solutions, solve x-6=0 and x+30=0.
x^{2}+24x=180
Anything plus zero gives itself.
x^{2}+24x-180=0
Subtract 180 from both sides.
a+b=24 ab=1\left(-180\right)=-180
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-180. To find a and b, set up a system to be solved.
-1,180 -2,90 -3,60 -4,45 -5,36 -6,30 -9,20 -10,18 -12,15
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -180.
-1+180=179 -2+90=88 -3+60=57 -4+45=41 -5+36=31 -6+30=24 -9+20=11 -10+18=8 -12+15=3
Calculate the sum for each pair.
a=-6 b=30
The solution is the pair that gives sum 24.
\left(x^{2}-6x\right)+\left(30x-180\right)
Rewrite x^{2}+24x-180 as \left(x^{2}-6x\right)+\left(30x-180\right).
x\left(x-6\right)+30\left(x-6\right)
Factor out x in the first and 30 in the second group.
\left(x-6\right)\left(x+30\right)
Factor out common term x-6 by using distributive property.
x=6 x=-30
To find equation solutions, solve x-6=0 and x+30=0.
x^{2}+24x=180
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^{2}+24x-180=180-180
Subtract 180 from both sides of the equation.
x^{2}+24x-180=0
Subtracting 180 from itself leaves 0.
x=\frac{-24±\sqrt{24^{2}-4\left(-180\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 24 for b, and -180 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-24±\sqrt{576-4\left(-180\right)}}{2}
Square 24.
x=\frac{-24±\sqrt{576+720}}{2}
Multiply -4 times -180.
x=\frac{-24±\sqrt{1296}}{2}
Add 576 to 720.
x=\frac{-24±36}{2}
Take the square root of 1296.
x=\frac{12}{2}
Now solve the equation x=\frac{-24±36}{2} when ± is plus. Add -24 to 36.
x=6
Divide 12 by 2.
x=-\frac{60}{2}
Now solve the equation x=\frac{-24±36}{2} when ± is minus. Subtract 36 from -24.
x=-30
Divide -60 by 2.
x=6 x=-30
The equation is now solved.
x^{2}+24x=180
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}+24x+12^{2}=180+12^{2}
Divide 24, the coefficient of the x term, by 2 to get 12. Then add the square of 12 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+24x+144=180+144
Square 12.
x^{2}+24x+144=324
Add 180 to 144.
\left(x+12\right)^{2}=324
Factor x^{2}+24x+144. 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+12\right)^{2}}=\sqrt{324}
Take the square root of both sides of the equation.
x+12=18 x+12=-18
Simplify.
x=6 x=-30
Subtract 12 from both sides of the equation.
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Simultaneous equation
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Limits
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