Question

first term =5
common difference =5
8th term of an arithmetic sequence is 45
find out the algebraic form of n th term ​

Answer 1

Step-by-step explanation:

We know that,

$tn = a + (n - 1)d$

So, here it is given that,

a = 5 , d = 5, t8 = 45

Substituting the above values,

$45 = 5 + (n - 1)5$

$45 = 5 + 5n - 5$

$45 = 5n$

$n = 9$

So, there are 9 terms in this A.P.