# What is the 25th term of the arithmetic sequence where a1 = 8 and a9 = 48?

##### 2 Answers

Jul 9, 2018

#### Explanation:

We know that ,

#color(blue)(n^(th)term " of the arithmetic sequence is :"#

#color(blue)(a_n=a_1+(n-1)d...to(I)#

We have ,

#color(red)(a_1=8 and a_9=48#

Using

Again using

#a_25=a_1+(25-1)d#

Jul 9, 2018

#### Explanation:

#"the n th term of an arithmetic sequence is"#

#â€¢color(white)(x)a_n=a_1+(n-1)d#

#"where d is the common difference"#

#"given "a_1=8" then"#

#a_9=8+8d=48rArr8d=40rArrd=5#

#a_(25)=8+(24xx5)=128#