a+b+c=79,a+b=53,b+c=45,a,b,c=?

Răspuns :

Adunam ultimele doua relatii:
a + b + b + c = 53 + 45 = 98
79 + b = 98
b = 98 - 79 = 19
a = 53 - 19 = 34
c = 45 - 19 = 26
a+b+c=79
a+b=53
c=79-53=26
b+c=45
a=79-45=34
b=53-34=19