Question

Алгебра........помогите.....

Answer 1

Смотри.......................

Answer 2

Ответ:

$\left\{\begin{array}{l}\dfrac{1}{x+y}+\dfrac{1}{x-y}=16\\\dfrac{5}{x+y}+\dfrac{6}{x-y}=89\end{array}\right\ \ \left\{\begin{array}{l}\dfrac{1}{x+y}=p\\\dfrac{1}{x-y}=t\end{array}\right\ \ \left\{\begin{array}{l}p+t=16\ |\cdot (-5)\\5p+6t=89\end{array}\right\ \ \oplus$

$\left\{\begin{array}{l}p=16-t\\t=9\end{array}\right\ \ \left\{\begin{array}{l}p=7\\t=9\end{array}\right\ \ \left\{\begin{array}{l}\dfrac{1}{x+y}=7\\\dfrac{1}{x-y}=9\end{array}\right\ \ \left\{\begin{array}{l}x+y=\dfrac{1}{7}\\\ x-y=\dfrac{1}{9} \end{array}\right\ \oplus \ \ominus$

$\left\{\begin{array}{l}2x=\dfrac{16}{63}\\\ \ 2y=\dfrac{2}{63}\end{array}\right\ \ \left\{\begin{array}{l}x=\dfrac{8}{63}\\\ \ y=\dfrac{1}{63}\end{array}\right$