a+b= 84 jika a:b = 5:9 maka b-a=...

a + b = 84
a = 84-b

a : b = 5 : 9
(84-b) : b = 5 : 9
5b = 9(84-b)
5b + 9b = 84x9
14b = 84 x 9
b = 84/14 x 9
b = 6 x 9 = 54
a = 5/9 x 54
a = 5 x 6 = 30

b - a = 54 - 30 = 24

Kelas 7 Matematika
Bab Persamaan Linear

a/b = 5/9
a = 5b/9

a + b = 84
5b/9 + b = 84

** dikali 9 **

5b + 9b = 756
14b = 756
b = 756/14
b = 54

a + b = 84
a + 54 = 84
a = 84 - 54
a = 30

b - a
= 54 - 30
= 24