Преобразуем (разложим на множители) левые части каждого уравнения данной системы.
1) 2х²-ху-3у²+х+у = (2х-3у)(х+у) + (х+у) = (х+у)(2х-3у+1)
2) 2х²-5ху+3у²+х-у = (2х-3у)(х-у) + (х-у) = (х-у)(2х-3у+1)
Получим систему:
![\begin {cases} (x+y)(2x-3y+1)=6 \\ (x-y)(2x-3y+1)=2 \end {cases} \begin {cases} (x+y)(2x-3y+1)=6 \\ (x-y)(2x-3y+1)=2 \end {cases}](https://tex.z-dn.net/?f=+%5Cbegin+%7Bcases%7D+%28x%2By%29%282x-3y%2B1%29%3D6+%5C%5C+%28x-y%29%282x-3y%2B1%29%3D2+%5Cend+%7Bcases%7D+)
Разделим первое уравнение на второе
![\begin {cases} \frac{x+y}{x-y}=3 \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \begin {cases} x+y=3(x-y) \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \\ \begin {cases} x+y=3x-3y \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \begin {cases} 2x=4y \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \\ \begin {cases} x=2y \\ (2y+y)(4y-3y+1)=6 \end {cases} \Rightarrow \begin {cases} x=2y \\ 3y(y+1)-6=0 \end {cases} \Rightarrow \begin {cases} \frac{x+y}{x-y}=3 \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \begin {cases} x+y=3(x-y) \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \\ \begin {cases} x+y=3x-3y \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \begin {cases} 2x=4y \\ (x+y)(2x-3y+1)=6 \end {cases} \Rightarrow \\ \begin {cases} x=2y \\ (2y+y)(4y-3y+1)=6 \end {cases} \Rightarrow \begin {cases} x=2y \\ 3y(y+1)-6=0 \end {cases} \Rightarrow](https://tex.z-dn.net/?f=+%5Cbegin+%7Bcases%7D+%5Cfrac%7Bx%2By%7D%7Bx-y%7D%3D3+%5C%5C+%28x%2By%29%282x-3y%2B1%29%3D6+%5Cend+%7Bcases%7D+%5CRightarrow+%5Cbegin+%7Bcases%7D+x%2By%3D3%28x-y%29+%5C%5C+%28x%2By%29%282x-3y%2B1%29%3D6+%5Cend+%7Bcases%7D+%5CRightarrow+%5C%5C+%5Cbegin+%7Bcases%7D+x%2By%3D3x-3y+%5C%5C+%28x%2By%29%282x-3y%2B1%29%3D6+%5Cend+%7Bcases%7D+%5CRightarrow++%5Cbegin+%7Bcases%7D+2x%3D4y+%5C%5C+%28x%2By%29%282x-3y%2B1%29%3D6+%5Cend+%7Bcases%7D+%5CRightarrow+%5C%5C+%5Cbegin+%7Bcases%7D+x%3D2y+%5C%5C+%282y%2By%29%284y-3y%2B1%29%3D6+%5Cend+%7Bcases%7D+%5CRightarrow+%5Cbegin+%7Bcases%7D+x%3D2y+%5C%5C+3y%28y%2B1%29-6%3D0+%5Cend+%7Bcases%7D+%5CRightarrow+)
3y²+3y-6=0
y²+y-2=0
y=1 или у=-2
Получим далее
![\begin {cases} y_1=1 \\ x_1=2 \end {cases} ;\ \ \begin {cases} y_2=-2 \\ x_2=-4 \end {cases} . \begin {cases} y_1=1 \\ x_1=2 \end {cases} ;\ \ \begin {cases} y_2=-2 \\ x_2=-4 \end {cases} .](https://tex.z-dn.net/?f=++%5Cbegin+%7Bcases%7D+y_1%3D1+%5C%5C+x_1%3D2+%5Cend+%7Bcases%7D+%3B%5C+%5C++%5Cbegin+%7Bcases%7D+y_2%3D-2+%5C%5C+x_2%3D-4+%5Cend+%7Bcases%7D+.+)
Ответ: (-4; -2), (2; 1).