Question

In an arithmetic sequence 5 th term is 16 and 9 th term is 28. a) Find the common difference b) What is the first term? c) Write the algebraic expression d) Find the sum of first 20 terms​

Answer 1

Answer:

a. 3

b. 4

c. 650

Step-by-step explanation:

t_n = a + ( n - 1 ) d

s_n = n / 2 [ 2a + ( n - 1 ) d ]