Solve for x
x=-52
x=46
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a+b=6 ab=-2392
To solve the equation, factor x^{2}+6x-2392 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.
-1,2392 -2,1196 -4,598 -8,299 -13,184 -23,104 -26,92 -46,52
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 -2392.
-1+2392=2391 -2+1196=1194 -4+598=594 -8+299=291 -13+184=171 -23+104=81 -26+92=66 -46+52=6
Calculate the sum for each pair.
a=-46 b=52
The solution is the pair that gives sum 6.
\left(x-46\right)\left(x+52\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=46 x=-52
To find equation solutions, solve x-46=0 and x+52=0.
a+b=6 ab=1\left(-2392\right)=-2392
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-2392. To find a and b, set up a system to be solved.
-1,2392 -2,1196 -4,598 -8,299 -13,184 -23,104 -26,92 -46,52
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 -2392.
-1+2392=2391 -2+1196=1194 -4+598=594 -8+299=291 -13+184=171 -23+104=81 -26+92=66 -46+52=6
Calculate the sum for each pair.
a=-46 b=52
The solution is the pair that gives sum 6.
\left(x^{2}-46x\right)+\left(52x-2392\right)
Rewrite x^{2}+6x-2392 as \left(x^{2}-46x\right)+\left(52x-2392\right).
x\left(x-46\right)+52\left(x-46\right)
Factor out x in the first and 52 in the second group.
\left(x-46\right)\left(x+52\right)
Factor out common term x-46 by using distributive property.
x=46 x=-52
To find equation solutions, solve x-46=0 and x+52=0.
x^{2}+6x-2392=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{-6±\sqrt{6^{2}-4\left(-2392\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 6 for b, and -2392 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-6±\sqrt{36-4\left(-2392\right)}}{2}
Square 6.
x=\frac{-6±\sqrt{36+9568}}{2}
Multiply -4 times -2392.
x=\frac{-6±\sqrt{9604}}{2}
Add 36 to 9568.
x=\frac{-6±98}{2}
Take the square root of 9604.
x=\frac{92}{2}
Now solve the equation x=\frac{-6±98}{2} when ± is plus. Add -6 to 98.
x=46
Divide 92 by 2.
x=-\frac{104}{2}
Now solve the equation x=\frac{-6±98}{2} when ± is minus. Subtract 98 from -6.
x=-52
Divide -104 by 2.
x=46 x=-52
The equation is now solved.
x^{2}+6x-2392=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}+6x-2392-\left(-2392\right)=-\left(-2392\right)
Add 2392 to both sides of the equation.
x^{2}+6x=-\left(-2392\right)
Subtracting -2392 from itself leaves 0.
x^{2}+6x=2392
Subtract -2392 from 0.
x^{2}+6x+3^{2}=2392+3^{2}
Divide 6, the coefficient of the x term, by 2 to get 3. Then add the square of 3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+6x+9=2392+9
Square 3.
x^{2}+6x+9=2401
Add 2392 to 9.
\left(x+3\right)^{2}=2401
Factor x^{2}+6x+9. 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+3\right)^{2}}=\sqrt{2401}
Take the square root of both sides of the equation.
x+3=49 x+3=-49
Simplify.
x=46 x=-52
Subtract 3 from both sides of the equation.
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