tolong bantu jawab pake cara

U6 = 17
a + (6 - 1)b = 17
a + 5b = 17

U10 = 33
a + 9b = 33

Eliminasi
a + 9b = 33
a + 5b = 17
----------------- -
4b = 16
b = 16/4 = 4

a + 5b = 17
a + (5 × 4) = 17
a + 20 = 17
a = 17 - 20 = -3

U15 = a + 14b
= -3 + (14 × 4)
= -3 + 56
= 53 (D)

Semoga membantu ^^

Matematika SMP Kelas 9
Barisan Bilangan dan Deret

Dik :
U6 = 17
U10 = 33

Dit : U15...?

Un = a + (n-1) b

U10 - U6 = 33 - 17
(a+9b) - (a+5b) = 22
4b = 16
b = 4

U6 = 17
a + 5b = 17
a + 5(4) = 17
a + 20 = 17
a = 17 - 20
a = -3

U15 = -3 + 14 (4)
U15 = -3 + 56
U15 = 53