Odpowiedzi

2009-12-08T18:24:03+01:00
X-y=3
-5x+10y=-10 /:(-10)

x-y=3
0,5x-y=1
Najlepsza Odpowiedź!
2009-12-08T18:26:52+01:00
A) {6x + y = 3
{3x + 1/2y = 5 / * (-2)

{6x +y =3
{-6x-y=-10

0=-7

b) {x-2y=-4
{0,5x+y=2 / * 2

{x-2y=-4
{x+2y=4
2x=0


c) {2x-1/2y =3 / * 2
{y-4x=-6

{-y+4x=6
{y-4x=-6
0=0

d) {x-y =3 / * 5
{-5x + 10y = - 10

{5x - 5y = 15
{-5x + 10 y = - 10

5y=5 / : 5
y=1
x=4


c)
2009-12-08T18:35:57+01:00
B)x-y=3
-5x+10y=-10

x=3+y
-5(3+y)+10y=-10

x=3+y
-15-5y+10y=-10

x=3+y
5y=-10+15

x=3+y
5y=5/:5

x=3+y

y=1
x=3+1

y=1
x=4

d)x-2y=-4
0,5x+y=2

x=-4+2y
0,5(-4+2y)+y=2

x=-4+2y
-2+y+y=2

x=-4+2y
2y=2+2

x=-4+2y
2y=4/:2

x=-4+2y
y=2

x=-4+2*2
y=2

x=-4+4
y=2

x=0
y=2