suatu banjarhitung suku kelima 20dan suku ketujuh 26 berapa beda dan suku pertamanya

Barder

b = 26- 20/ 7-5
b = 6/2 = 3

a + 4b = U5
a + 12 = 20
a = 8

Diket:
U5 = 20
U7 = 26

Tanya: B dan U1?

Jawab;
[tex] \frac{26-20}{7-5}= \frac{6}{2} = 3 [/tex]
U5 = a + 4b
20 = a + 4 (3)
20 = a + 12
a = 20 - 12
a = 8