Odpowiedzi

2009-12-13T17:18:07+01:00
A)2x+3y=0,5
3x+y=-1/* (-3)
2x+3y=0.5
-9x-3y=3 +3y i -3y skreśl
-7x=3.5/: (-7)
x=-0,5
2x
2009-12-13T17:26:53+01:00
2x+3y=0,5
3x+y=-1
----------------
5x+4y=-0,5
5x=-0,5-4y
x=-0,1 - 0,8y

5x+4y=-0,5
4y=-0,5-5x
y= -0,125 - 1,25 (-0,1 - 0,8y)
y= -0,125 +0,125 + 1y
y-y=0
0=0

x=-0,1 - 0,8y
x=-0,1
y=0


b)2x+y=14
8x+0,5y=35
-----------------
10x+1,5y=49
10x=49-1,5y
x=4,9-0,15y

10x+1,5y=49
1,5y=49-10x
y=98/3 - 20/3 x
y=98/3 - 20/3 (4,9-0,15y)
y=98/3 - 98/3 +1y
y-y=0
0=0

x=4,9-0,15y
x=4,9
y=0


c)3x+4y=2
5x+7y=1
------------
8x+11y=3
8x=3-11y
x=3/8 - 11/8 y

8x+11y=3
11y=3-8x
y=3/11 - 8/11 x
y=3/11 - 8/11 ( 3/8 - 11/8 y)
y= 3/11- 3/11 + 1y
y-y=0
0=0

x=3/8 - 11/8 y
x=3/8
y=0
1 5 1