Factor
6\left(m+2\right)\left(m+6\right)
Evaluate
6\left(m+2\right)\left(m+6\right)
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6\left(m^{2}+8m+12\right)
Factor out 6.
a+b=8 ab=1\times 12=12
Consider m^{2}+8m+12. Factor the expression by grouping. First, the expression needs to be rewritten as m^{2}+am+bm+12. To find a and b, set up a system to be solved.
1,12 2,6 3,4
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 12.
1+12=13 2+6=8 3+4=7
Calculate the sum for each pair.
a=2 b=6
The solution is the pair that gives sum 8.
\left(m^{2}+2m\right)+\left(6m+12\right)
Rewrite m^{2}+8m+12 as \left(m^{2}+2m\right)+\left(6m+12\right).
m\left(m+2\right)+6\left(m+2\right)
Factor out m in the first and 6 in the second group.
\left(m+2\right)\left(m+6\right)
Factor out common term m+2 by using distributive property.
6\left(m+2\right)\left(m+6\right)
Rewrite the complete factored expression.
6m^{2}+48m+72=0
Quadratic polynomial can be factored using the transformation ax^{2}+bx+c=a\left(x-x_{1}\right)\left(x-x_{2}\right), where x_{1} and x_{2} are the solutions of the quadratic equation ax^{2}+bx+c=0.
m=\frac{-48±\sqrt{48^{2}-4\times 6\times 72}}{2\times 6}
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.
m=\frac{-48±\sqrt{2304-4\times 6\times 72}}{2\times 6}
Square 48.
m=\frac{-48±\sqrt{2304-24\times 72}}{2\times 6}
Multiply -4 times 6.
m=\frac{-48±\sqrt{2304-1728}}{2\times 6}
Multiply -24 times 72.
m=\frac{-48±\sqrt{576}}{2\times 6}
Add 2304 to -1728.
m=\frac{-48±24}{2\times 6}
Take the square root of 576.
m=\frac{-48±24}{12}
Multiply 2 times 6.
m=-\frac{24}{12}
Now solve the equation m=\frac{-48±24}{12} when ± is plus. Add -48 to 24.
m=-2
Divide -24 by 12.
m=-\frac{72}{12}
Now solve the equation m=\frac{-48±24}{12} when ± is minus. Subtract 24 from -48.
m=-6
Divide -72 by 12.
6m^{2}+48m+72=6\left(m-\left(-2\right)\right)\left(m-\left(-6\right)\right)
Factor the original expression using ax^{2}+bx+c=a\left(x-x_{1}\right)\left(x-x_{2}\right). Substitute -2 for x_{1} and -6 for x_{2}.
6m^{2}+48m+72=6\left(m+2\right)\left(m+6\right)
Simplify all the expressions of the form p-\left(-q\right) to p+q.
x ^ 2 +8x +12 = 0
Quadratic equations such as this one can be solved by a new direct factoring method that does not require guess work. To use the direct factoring method, the equation must be in the form x^2+Bx+C=0.This is achieved by dividing both sides of the equation by 6
r + s = -8 rs = 12
Let r and s be the factors for the quadratic equation such that x^2+Bx+C=(x−r)(x−s) where sum of factors (r+s)=−B and the product of factors rs = C
r = -4 - u s = -4 + u
Two numbers r and s sum up to -8 exactly when the average of the two numbers is \frac{1}{2}*-8 = -4. You can also see that the midpoint of r and s corresponds to the axis of symmetry of the parabola represented by the quadratic equation y=x^2+Bx+C. The values of r and s are equidistant from the center by an unknown quantity u. Express r and s with respect to variable u. <div style='padding: 8px'><img src='https://opalmath.azureedge.net/customsolver/quadraticgraph.png' style='width: 100%;max-width: 700px' /></div>
(-4 - u) (-4 + u) = 12
To solve for unknown quantity u, substitute these in the product equation rs = 12
16 - u^2 = 12
Simplify by expanding (a -b) (a + b) = a^2 – b^2
-u^2 = 12-16 = -4
Simplify the expression by subtracting 16 on both sides
u^2 = 4 u = \pm\sqrt{4} = \pm 2
Simplify the expression by multiplying -1 on both sides and take the square root to obtain the value of unknown variable u
r =-4 - 2 = -6 s = -4 + 2 = -2
The factors r and s are the solutions to the quadratic equation. Substitute the value of u to compute the r and s.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}