Evaluate
\frac{8c^{2}}{c^{2}-9}
Factor
\frac{8c^{2}}{c^{2}-9}
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\frac{4c\left(c+3\right)}{\left(c-3\right)\left(c+3\right)}+\frac{4c\left(c-3\right)}{\left(c-3\right)\left(c+3\right)}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of c-3 and c+3 is \left(c-3\right)\left(c+3\right). Multiply \frac{4c}{c-3} times \frac{c+3}{c+3}. Multiply \frac{4c}{c+3} times \frac{c-3}{c-3}.
\frac{4c\left(c+3\right)+4c\left(c-3\right)}{\left(c-3\right)\left(c+3\right)}
Since \frac{4c\left(c+3\right)}{\left(c-3\right)\left(c+3\right)} and \frac{4c\left(c-3\right)}{\left(c-3\right)\left(c+3\right)} have the same denominator, add them by adding their numerators.
\frac{4c^{2}+12c+4c^{2}-12c}{\left(c-3\right)\left(c+3\right)}
Do the multiplications in 4c\left(c+3\right)+4c\left(c-3\right).
\frac{8c^{2}}{\left(c-3\right)\left(c+3\right)}
Combine like terms in 4c^{2}+12c+4c^{2}-12c.
\frac{8c^{2}}{c^{2}-9}
Expand \left(c-3\right)\left(c+3\right).
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