Question

помогите, пожалуйста​

Answer 1

$\begin{cases}x+y=-6\\xy=-16 \end{cases}\\\\\begin{cases} y=-x-6\\x (-x-6)+16=0 \end{cases} \\\\\begin{cases} y=-x-6\\ -x^2-6x+16=0 \end{cases}\\\\-x^2-6x+16=0\ \ /*(-1)\\x^2+6x-16=0\\\\D=b^2-4ac=6^2-4*1*(-16)=36+64=100$

$x_{1}=\frac{-b-\sqrt{D}}{2a}=\frac{-6-\sqrt{100}}{2*1}=\frac{-6-10}{2 }=\frac{-16}{2}=-8\\\\x_{2}=\frac{-b+\sqrt{D}}{2a}=\frac{-6+\sqrt{100}}{2*1}=\frac{-6+10}{2 }=\frac{4}{2}=2\\\\\begin{cases} x=-8 \\ y=-x-6 \end{cases}\ \ \ \vee \ \ \ \begin{cases} x=2 \\ y=-x-6 \end{cases}\\\\\begin{cases} x=-8 \\ y=8-6 \end{cases}\ \ \ \vee \ \ \ \begin{cases} x=2 \\ y=-2-6 \end{cases}\\\\\begin{cases} x=-8 \\ y=2 \end{cases}\ \ \ \vee \ \ \ \begin{cases} x=2 \\ y=-8 \end{cases}$