Răspuns :
a + b + c = 48
a + b = 26 => c = 48 - 26 = 22
a + b + c = 48
b + c = 28 => a = 48 - 28 = 20
20 + b + 22 = 48
42 + b = 48
b = 48 - 42
b = 6
a = 20
b = 6
c = 22
V. 20 + 6 + 22 = 48
a+b+c=48
a+b=26...=> 26+c=48...=> c=48-26...=> c=22
b+c=28...=> a+28=48...=> a=48-28...=> a=20
c+a=20+22...=> c+a=42...=> b+42=48...=> b=48-42...=> b=6
20+6+22=26+22=48