Răspuns :
x+y+z=42
x-t=3
x=t+3
y-t=5
y=t+5
z-t=7
z=t+7
inlocuim in x+y+z=42
t+3+t+5+t+7=42
3t+15=42
3t=42-15
3t=27
t=27:3
t=9
x=9+3=12
y=9+5=14
z=9+7=16
Proba:14+16+12=30+12=42
x-t=3
x=t+3
y-t=5
y=t+5
z-t=7
z=t+7
inlocuim in x+y+z=42
t+3+t+5+t+7=42
3t+15=42
3t=42-15
3t=27
t=27:3
t=9
x=9+3=12
y=9+5=14
z=9+7=16
Proba:14+16+12=30+12=42
I nr /----/ +3
II nr /----/+5 } 42
III nr /----/+7
3+5+7 = 15
42 - 15 = 27
27:3 = 9
I nr = 9+3 = 12
II nr = 9+5 = 14
II nr = 9+7= 16
12+14+16 = 42
II nr /----/+5 } 42
III nr /----/+7
3+5+7 = 15
42 - 15 = 27
27:3 = 9
I nr = 9+3 = 12
II nr = 9+5 = 14
II nr = 9+7= 16
12+14+16 = 42