bantuin bro, soal matematika

bil 1 = a
bil 2 = b = a + 4
bil 3 = c = c - 17 = a

a + b + c = 49
a + a+4+ a = 49
3a + 4 = 49
3a = 49-4
3a = 45
a = 45/3
a = 15

b = a + 4
b = 15 + 4
b = 19

c - 17 = a
c - 17 = 15
c = 15 + 17
c = 32

ketiga bilangan tsb adalah = 15 , 19, 32

a + b + c = 49
15 + 19 + (32 - 17) = 49