Odpowiedzi

2009-12-26T22:03:23+01:00
X+2
-------- - 2y =5
5

y+2
x - -------- =3
6
_______________________

x+2 - 10y =25

6x - y-2 =18
_______________________
x - 10y =23

6x - y =20
_______________________
x - 10y =23

-60x + 10y =-200
_______________________
-59x=-177
_______________________
x=3
_______________________
x - 10y =23
_______________________
3-10y=23
_______________________
-10y=20
_______________________
y=-2
2009-12-26T22:24:44+01:00
X+2
-------- - 2y =5 /*5
5

y+2
x - -------- =3/*6
6

x + 2 - 10y = 25
6x - y - 2 = 18
Metoda przeciwnych współczynników
x - 10y = 23
6x - y =20 / * (-10)

x - 10y = 23
-60x + 10y = -200

-59x = -177 /:(-59)
x = 3
Podstawiamy wiadomą x do równania I

x - 10y = 23
3 - 10y = 23
-10y = 20 /:(-10)
y = -2

Odp. X = 3, y = -2
2009-12-26T22:55:13+01:00
(x+2)/5 - 2y=5 /*5
x- (y+2)/6=3 /*6

x+2-10y=25
6x-(y+2)=18

x-10y=25-2
6x-y-2=18

x-10y=23
6x-y=20 /*(-10)

x-10y=23
-60x+10y=-200
-------------------
-59x=-177 /:(-59)
x=3

6x-y=20
6*3 -y=20
18-y=20
-y=20-18
-y=2
y=-2