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a+b=76 ab=-4332
To solve the equation, factor x^{2}+76x-4332 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.
-1,4332 -2,2166 -3,1444 -4,1083 -6,722 -12,361 -19,228 -38,114 -57,76
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 -4332.
-1+4332=4331 -2+2166=2164 -3+1444=1441 -4+1083=1079 -6+722=716 -12+361=349 -19+228=209 -38+114=76 -57+76=19
Calculate the sum for each pair.
a=-38 b=114
The solution is the pair that gives sum 76.
\left(x-38\right)\left(x+114\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=38 x=-114
To find equation solutions, solve x-38=0 and x+114=0.
a+b=76 ab=1\left(-4332\right)=-4332
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-4332. To find a and b, set up a system to be solved.
-1,4332 -2,2166 -3,1444 -4,1083 -6,722 -12,361 -19,228 -38,114 -57,76
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 -4332.
-1+4332=4331 -2+2166=2164 -3+1444=1441 -4+1083=1079 -6+722=716 -12+361=349 -19+228=209 -38+114=76 -57+76=19
Calculate the sum for each pair.
a=-38 b=114
The solution is the pair that gives sum 76.
\left(x^{2}-38x\right)+\left(114x-4332\right)
Rewrite x^{2}+76x-4332 as \left(x^{2}-38x\right)+\left(114x-4332\right).
x\left(x-38\right)+114\left(x-38\right)
Factor out x in the first and 114 in the second group.
\left(x-38\right)\left(x+114\right)
Factor out common term x-38 by using distributive property.
x=38 x=-114
To find equation solutions, solve x-38=0 and x+114=0.
x^{2}+76x-4332=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{-76±\sqrt{76^{2}-4\left(-4332\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 76 for b, and -4332 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-76±\sqrt{5776-4\left(-4332\right)}}{2}
Square 76.
x=\frac{-76±\sqrt{5776+17328}}{2}
Multiply -4 times -4332.
x=\frac{-76±\sqrt{23104}}{2}
Add 5776 to 17328.
x=\frac{-76±152}{2}
Take the square root of 23104.
x=\frac{76}{2}
Now solve the equation x=\frac{-76±152}{2} when ± is plus. Add -76 to 152.
x=38
Divide 76 by 2.
x=-\frac{228}{2}
Now solve the equation x=\frac{-76±152}{2} when ± is minus. Subtract 152 from -76.
x=-114
Divide -228 by 2.
x=38 x=-114
The equation is now solved.
x^{2}+76x-4332=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}+76x-4332-\left(-4332\right)=-\left(-4332\right)
Add 4332 to both sides of the equation.
x^{2}+76x=-\left(-4332\right)
Subtracting -4332 from itself leaves 0.
x^{2}+76x=4332
Subtract -4332 from 0.
x^{2}+76x+38^{2}=4332+38^{2}
Divide 76, the coefficient of the x term, by 2 to get 38. Then add the square of 38 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+76x+1444=4332+1444
Square 38.
x^{2}+76x+1444=5776
Add 4332 to 1444.
\left(x+38\right)^{2}=5776
Factor x^{2}+76x+1444. 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+38\right)^{2}}=\sqrt{5776}
Take the square root of both sides of the equation.
x+38=76 x+38=-76
Simplify.
x=38 x=-114
Subtract 38 from both sides of the equation.