Question

The 10th term of an arithmetic sequence is 20 and

(a) What is its common difference?

What is its 30th term?

its 20th term is 10.

Which is the first negative term of this sequence ?​

Answer 1

Step-by-step explanation:

a+9d =20

a+19d=10

by eliminating.. we will get

-10d=10

d=-1 (common difference)

an =a + (n-1) d

-1 = 29 + (n-1) -1

-30 = ( n-1) -1

30 = n-1

n=31