Question

5ас2/а2-9с2*а-3с/ас при а=8,3 с=-3,6

Answer 1

$\frac{5ac^2}{a^2-9c^2} * \frac{a-3c}{ac}= \frac{5ac^2}{(a-3c)(a+3c)}* \frac{a-3c}{ac}= \frac{5c}{a+3c}\\\\a=8,3\\c=-3,6\\\\ \frac{5*(-3,6)}{8,3+3(-3,6)}= \frac{-18}{8,3-10,8}= \frac{-18}{-2,5}=7,2$