Odpowiedzi

2010-03-29T18:16:18+02:00
X=15-y
17(15-y)+20y= 290

x=15-y
255-17y+20y=290

x=15-y
3y=290-255

x=15-y
3y=35/:3

x=15-y
y=11i 2/3

x=15-11 2/3
x=10/3= 3i 1/3
2010-03-29T18:27:36+02:00
X+y=15
17x+20y=290

y=15-x
17x+20(15-x)=290

y=15-x
17x+300-20x=290

y=15-x
17x-20x=290-300

y=15-x
-3x=-10

y=15-x
x=3 1/3

y=15- 3 1/3
x=3

y=11 2/3
x=3