Solve for x
x=-12
x=-2
Graph
Share
Copied to clipboard
x^{2}+14x+24=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
a+b=14 ab=24
To solve the equation, factor x^{2}+14x+24 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.
1,24 2,12 3,8 4,6
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 24.
1+24=25 2+12=14 3+8=11 4+6=10
Calculate the sum for each pair.
a=2 b=12
The solution is the pair that gives sum 14.
\left(x+2\right)\left(x+12\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=-2 x=-12
To find equation solutions, solve x+2=0 and x+12=0.
x^{2}+14x+24=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
a+b=14 ab=1\times 24=24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+24. To find a and b, set up a system to be solved.
1,24 2,12 3,8 4,6
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 24.
1+24=25 2+12=14 3+8=11 4+6=10
Calculate the sum for each pair.
a=2 b=12
The solution is the pair that gives sum 14.
\left(x^{2}+2x\right)+\left(12x+24\right)
Rewrite x^{2}+14x+24 as \left(x^{2}+2x\right)+\left(12x+24\right).
x\left(x+2\right)+12\left(x+2\right)
Factor out x in the first and 12 in the second group.
\left(x+2\right)\left(x+12\right)
Factor out common term x+2 by using distributive property.
x=-2 x=-12
To find equation solutions, solve x+2=0 and x+12=0.
x^{2}+14x+24=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
x=\frac{-14±\sqrt{14^{2}-4\times 24}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 14 for b, and 24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-14±\sqrt{196-4\times 24}}{2}
Square 14.
x=\frac{-14±\sqrt{196-96}}{2}
Multiply -4 times 24.
x=\frac{-14±\sqrt{100}}{2}
Add 196 to -96.
x=\frac{-14±10}{2}
Take the square root of 100.
x=-\frac{4}{2}
Now solve the equation x=\frac{-14±10}{2} when ± is plus. Add -14 to 10.
x=-2
Divide -4 by 2.
x=-\frac{24}{2}
Now solve the equation x=\frac{-14±10}{2} when ± is minus. Subtract 10 from -14.
x=-12
Divide -24 by 2.
x=-2 x=-12
The equation is now solved.
x^{2}+14x+24=0
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
x^{2}+14x=-24
Subtract 24 from both sides. Anything subtracted from zero gives its negation.
x^{2}+14x+7^{2}=-24+7^{2}
Divide 14, the coefficient of the x term, by 2 to get 7. Then add the square of 7 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+14x+49=-24+49
Square 7.
x^{2}+14x+49=25
Add -24 to 49.
\left(x+7\right)^{2}=25
Factor x^{2}+14x+49. 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+7\right)^{2}}=\sqrt{25}
Take the square root of both sides of the equation.
x+7=5 x+7=-5
Simplify.
x=-2 x=-12
Subtract 7 from both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}