Question

розв'яжіть систему рівнянь х-у=3 х2+у2=17​

Answer 1

Ответ:

Метод подстановки решения систем уравнений .

$\left\{\begin{array}{l}\bf x-y=3\\\bf x^2+y^2=17\end{array}\right\ \ \left\{\begin{array}{l}\bf y=x-3\\\bf x^2+(x-3)^2=17\end{array}\right\ \ \left\{\begin{array}{l}\bf y=x-3\\\bf x^2+x^2-6x+9-17=0\end{array}\right\\\\\\\left\{\begin{array}{l}\bf y=x-3\\\bf 2x^2-6x-8=0\end{array}\right\ \ \left\{\begin{array}{l}\bf y=x-3\\\bf x^2-3x-4=0\end{array}\right\ \ \left\{\begin{array}{l}\bf y=x-3\\\bf (x+1)(x-4)=0\end{array}\right$  

$\left\{\begin{array}{l}\bf y=x-3\\\bf x_1=-1\ ,\ x_2=4\end{array}\right\ \ \left\{\begin{array}{l}\bf y_1=-4\ ,\ y_2=1\\\bf x_1=-1\ ,\ x_2=4\end{array}\right\\\\\\\bf Otvet:\ (-1;-4\, )\ ,\ (\ 4\ ;\ 1\ )\ .$