Yang bisa bantu jawab pake caranya. makasih

2.
U2 = 5
U5 = 14

Jawaban
U2 - U5 = 5 - 14
b - 4b = -9
-3b = - 9
b = 9/3
b = 3

Maka nilai a:
U2 = a + b
5 = a + 3
5-3 = a
2 = a

Jadi, U20:
U20 = a + 19b
U20 = 2 + 19(3)
U20 = 2 + 57
U20 = 59

Ma610
S20:
S20 = n/2 (a + U20)
S20 = 20/2 (2 + 59)
S20 = 10(61)
S20 = 610

Jawaban c