Odpowiedzi

2009-12-20T18:32:55+01:00
7x + 7y = 21
2x+5y+8 = 14

7x=21 - 7y
2x+5y + 8=14

x=3-y
6-2y+5y+8=14
3y=0
y=0
x=3


5x- y = 1.5 /*2
3x+6y= 4.2/*5

12x-2y=3 /*15
15x+30y=21

180x-30y=45
15x + 30y=21
____________+
195x=66
x=22/65

y=-22/33+1,5


2x+y=-1
3y-x=-17 /*2

2x+y=-1
-2x+6y=-34
__________
7y=-35
y=-5
2x-5=-1
2x=4
x=2


2x+y=5 /-1
2x+y=7

-2x -y = -5
2x+y=7
____________
0=-2
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