Răspuns :
r + v = 15 adica r = 15 - v
a + v = 14
a + r = 11 adica a + 15 - v = 11 adica v - a = 15 - 11 adica v - a = 4
v = 4 + a inlocuim in a doua ecuatie
a + 4 + a = 14 adica
2a = 14 - 4
2a = 10
a = 10 : 2
a = 5
v = 4 + 5
v = 9
r = 15 - 9
r = 6
a + v = 14
a + r = 11 adica a + 15 - v = 11 adica v - a = 15 - 11 adica v - a = 4
v = 4 + a inlocuim in a doua ecuatie
a + 4 + a = 14 adica
2a = 14 - 4
2a = 10
a = 10 : 2
a = 5
v = 4 + 5
v = 9
r = 15 - 9
r = 6