Question

Ajutatima va rog sa rezolv sistemul:Va Rog Mult

{x^2-xy-y^2=5
x-y=2


(^2 - inseamna la puterea a doua)

Answer 1

[tex] \left \{ {{x^2-xy-y^2=5} \atop {x-y=2}} \right. \ \textless \ =\ \textgreater \ \left \{ {{(2+y)^2-y(2+y)-(2+y)^2=5} \atop {x=2+y}} \right. \ \textless \ =\ \textgreater \ \\\left \{ {{4+4y+y^2-2y-y^2-4-4y-y^2=5} \atop {x=2+y}} \right. \ \textless \ =\ \textgreater \ \left \{ {{-y^2-2y=5|*(-1)} \atop {x=2+y}} \right. \ \textless \ =\ \textgreater \ \left \{ {{y^2+2y=-5} \atop {x=2+y}} \right.\\ \ \textless \ =\ \textgreater \ \left \{ {{y(y+2)=5} \atop {x=2+y}} \right. \ \textless \ =\ \textgreater \ \left \{ {{y_1=0} \atop {x_1=2}} \right. \ \textless \ =\ \textgreater \ \left \{ {{y_2=-7 \atop {x_2=-5}} \right. [/tex]