Evaluate
-\frac{20}{\left(x-6\right)\left(x+4\right)}
Expand
-\frac{20}{\left(x-6\right)\left(x+4\right)}
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\frac{\left(x+6\right)\left(x-6\right)}{\left(x-6\right)\left(x+4\right)}-\frac{\left(x-4\right)\left(x+4\right)}{\left(x-6\right)\left(x+4\right)}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x+4 and x-6 is \left(x-6\right)\left(x+4\right). Multiply \frac{x+6}{x+4} times \frac{x-6}{x-6}. Multiply \frac{x-4}{x-6} times \frac{x+4}{x+4}.
\frac{\left(x+6\right)\left(x-6\right)-\left(x-4\right)\left(x+4\right)}{\left(x-6\right)\left(x+4\right)}
Since \frac{\left(x+6\right)\left(x-6\right)}{\left(x-6\right)\left(x+4\right)} and \frac{\left(x-4\right)\left(x+4\right)}{\left(x-6\right)\left(x+4\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{x^{2}-6x+6x-36-x^{2}-4x+4x+16}{\left(x-6\right)\left(x+4\right)}
Do the multiplications in \left(x+6\right)\left(x-6\right)-\left(x-4\right)\left(x+4\right).
\frac{-20}{\left(x-6\right)\left(x+4\right)}
Combine like terms in x^{2}-6x+6x-36-x^{2}-4x+4x+16.
\frac{-20}{x^{2}-2x-24}
Expand \left(x-6\right)\left(x+4\right).
\frac{\left(x+6\right)\left(x-6\right)}{\left(x-6\right)\left(x+4\right)}-\frac{\left(x-4\right)\left(x+4\right)}{\left(x-6\right)\left(x+4\right)}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x+4 and x-6 is \left(x-6\right)\left(x+4\right). Multiply \frac{x+6}{x+4} times \frac{x-6}{x-6}. Multiply \frac{x-4}{x-6} times \frac{x+4}{x+4}.
\frac{\left(x+6\right)\left(x-6\right)-\left(x-4\right)\left(x+4\right)}{\left(x-6\right)\left(x+4\right)}
Since \frac{\left(x+6\right)\left(x-6\right)}{\left(x-6\right)\left(x+4\right)} and \frac{\left(x-4\right)\left(x+4\right)}{\left(x-6\right)\left(x+4\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{x^{2}-6x+6x-36-x^{2}-4x+4x+16}{\left(x-6\right)\left(x+4\right)}
Do the multiplications in \left(x+6\right)\left(x-6\right)-\left(x-4\right)\left(x+4\right).
\frac{-20}{\left(x-6\right)\left(x+4\right)}
Combine like terms in x^{2}-6x+6x-36-x^{2}-4x+4x+16.
\frac{-20}{x^{2}-2x-24}
Expand \left(x-6\right)\left(x+4\right).
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Simultaneous equation
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Limits
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