Respuesta :

Step-by-step explanation:

usually Brunei do like this:

y=3-x

then subs this eqn to the second eqn

sorry if I'm wrong :(

x-y=3

x-y-3=3-3
x-y=0

x2 - xy-2y2 - 7 =0
y/x = 2x-y/x+4y