dalam suatu bilangan aritmatika diketahui u5 = 7 dan u8 = 16 Tentukan u10

U8 = a + 7b = 16
U5 = a + 4b = 7

Menggunakan metode subtitusi
a + 4b = 7
a = 7 - 4b

a + 7b = 16
(7 - 4b) + 7b = 16
3b = 9
b = 3

a = 7 - 4b
a = 7 - 4(3)
a = 7 - 12
a = -5

U5 = a+4b = 7
U8 = a+7b =16
.................... -
- 3b = - 9
b = 3

a+4b =7
a + 4.3 =7
a = 7-12
a = - 5

U10 = a +9b = - 5 + 9.3 = - 5 +27 = 22
Jadi U10 =22