Odpowiedzi

2010-01-11T19:07:48+01:00
X- wiek ojca
y+28 -wiek syna

y+28=x
x=3y

y-x=-28/3
x-3y=0

3y-3x=-84
-3y+x=0
---------------
0 -2x=-84//-2

x=42
y+28=42

x=42
y=42-28

x=42
y=14