Odpowiedzi

2009-12-07T17:41:02+01:00
(x + 2)(y + 5) = xy + 65
(x - 5)(y - 2) = xy - 54

xy + 2y + 5x + 10 = xy + 65
xy - 5y - 2x + 10 = xy - 54

5x + 2y = 65 |* 2
-2x - 5y = - 54 |*5

10x + 4y = 130
-10x - 25y = - 270

-21y = - 140 |: (-21)
y = 6⅔

5x + 2* 6⅔ = 65
5x + 2* 20/3 = 65
5x + 40/3 = 65
5x = 65 - 13i1/3
5x = 51i2/3 |:5
x = 10⅓

5 1 5
2009-12-07T17:44:02+01:00
(x+2)(y+5)=xy+65
(x-5)(y-2)=xy-54



x=15
y=10
4 1 4