Evaluate
\frac{8}{\left(a-5\right)\left(a+4\right)}
Expand
\frac{8}{a^{2}-a-20}
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\frac{10\left(8a-80\right)}{\left(a^{2}-a-20\right)\left(10a-100\right)}
Divide \frac{10}{a^{2}-a-20} by \frac{10a-100}{8a-80} by multiplying \frac{10}{a^{2}-a-20} by the reciprocal of \frac{10a-100}{8a-80}.
\frac{8\times 10\left(a-10\right)}{10\left(a-10\right)\left(a-5\right)\left(a+4\right)}
Factor the expressions that are not already factored.
\frac{2\times 4}{\left(a-5\right)\left(a+4\right)}
Cancel out 2\times 5\left(a-10\right) in both numerator and denominator.
\frac{8}{a^{2}-a-20}
Expand the expression.
\frac{10\left(8a-80\right)}{\left(a^{2}-a-20\right)\left(10a-100\right)}
Divide \frac{10}{a^{2}-a-20} by \frac{10a-100}{8a-80} by multiplying \frac{10}{a^{2}-a-20} by the reciprocal of \frac{10a-100}{8a-80}.
\frac{8\times 10\left(a-10\right)}{10\left(a-10\right)\left(a-5\right)\left(a+4\right)}
Factor the expressions that are not already factored.
\frac{2\times 4}{\left(a-5\right)\left(a+4\right)}
Cancel out 2\times 5\left(a-10\right) in both numerator and denominator.
\frac{8}{a^{2}-a-20}
Expand the expression.
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}