Question

Помогите пожалуйста.Заранее спасибо.

Answer 1

$\dfrac{2a^{2}+12a }{a^{2}-25 }+\dfrac{8a-9}{25-a^{2} }-\dfrac{a^{2}+14a-16 }{a^{2}-25 } = \dfrac{2a^{2}+12a }{a^{2}-25 }-\dfrac{8a-9}{a^{2}-25 }-\dfrac{a^{2}+14a-16 }{a^{2}-25 } =\\\\\\= \dfrac{2a^{2}+12a-8a+9-a^{2}-14a+16}{a^{2}-25 }=\dfrac{a^{2}-10a+25 }{a^{2}-25 } =\\\\\\=\dfrac{(a-5)^{2} }{(a-5)(a+5)}=\boxed{\dfrac{a-5}{a+5}}$