Решите систему уравнений ху=-2; х+у=1

Решите задачу:

$\begin{cases}xy = -2\\ x + y = 1\end{cases}\\\\ \begin{cases}x(1 - x) = x - x^2 = -2\\ y = 1 - x\end{cases}\\\\ \begin{cases}-x^2 + x + 2 = 0\\ y = 1 - x\end{cases}\\\\ \begin{cases}-x^2 + 2x - x + 2 = x(2- x) + (2 - x) = (x + 1)(2 - x) = 0\\ y = 1 - x\end{cases}\\\\ \begin{cases}x_1 = -1\\ y_1 = 1 - (-1) = 2\end{cases} \ \begin{cases}x_2 = 2\\ y_2 = 1 - 2 = -1\end{cases}\\\\ \mathbb{OTBET:} \ (-1; 2), \ (2; -1) .$