divide : algebraic fractions

Answer: C
Step-by-step explanation:
[tex]\frac{r+5}{r^{2}+5r-14}[/tex] ÷ [tex]\frac{r^{2}+4r-21}{r-2}[/tex]
= [tex]\frac{r+5}{r^{2}+5r-14}[/tex] * [tex]\frac{r-2}{r^{2}+4r-21}[/tex]
= [tex]\frac{r+5}{(r+7)(r-2)}[/tex] * [tex]\frac{r-2}{(r+7)(r-3)}[/tex]
= [tex]\frac{(r+5)(r-2)}{(r+7)(r-2)(r+7)(r-3)}[/tex]
= [tex]\frac{r+5}{(r+7)(r+7)(r-3)}[/tex]