Odpowiedzi

2009-12-13T17:56:42+01:00
{x+2y=9
{y-1=3x

{x+2y=9
{y=3x+1

{x+2(2x+1)=9
{y=3x+1

{x+4x+2=9
{y=3x+1

{x+4x=9-2
{y=3x+1

{5x=7 /:5
{y=3x+1

{x=⅕
{y=1⅗
Najlepsza Odpowiedź!
2009-12-13T17:58:56+01:00
Mamy układ:

{ x+2y=9
{y-1=3x

{ x+2y=9
{-3x+y=1

{x=9-2y
{-3(9-2y)+y=1

{x=9-2y
(-27+6y+y=1

{x=9-2y
{7y=28

{x=9-2y
{y=4

{x=9-2(4)
{y=4

{x=1
{y=4


2009-12-13T18:00:44+01:00
A) x+2y=9
y-1=3x

x +2y = 9 /*3
-3x+y =1
<metoda preciwnych wspolczynnikow>
3x +6y = 27
-3x +y =1

7y = 28
y=4


y=4
x+2*4 = 9

y=4
x= 1

:)