Odpowiedź :
[tex]7 {x}^{2} - xy + 35xy - 5 {y}^{2} = 7{x}^{2} + 34xy - 5 {y}^{2} [/tex]
[tex]2 {x}^{2} + 2xy - xy - {y}^{2} = 2 {x}^{2} + xy - {y}^{2} [/tex]
[tex]2 {xy}^{2} 6 {x}^{2}y - 2 {x}^{2} y - 6 {x}^{2} [/tex]
W ostatnim a to x a b to y | a=x b = y