Odpowiedzi

2009-12-10T15:09:47+01:00
A){x-y=4|*2
{x+2y=-7
{2x-2y=8
{x+2y=-7
2x=1|:2
x=
2009-12-10T15:11:05+01:00
A)
x-y=4
x+2y=-7 /razy -1

x-y=-1
-x-2y=7

-3y=7 /podzilić -3
y=2⅓

x-2⅓=4
x=4+2⅓
x=6⅓