Question

In ap , if the common difference d is equal to -4 and the seventh term a7 is 4 , then find the first term?

Answer 1

Answer: a =28

Step-by-step explanation:

Answer 2

Given: common difference = - 4 and 7th term is 4

To find: first term

Step-by-step explanation:

In mathematics arithmetic, progression/sequence is a number of difference between the consecutive term is the same which is called common difference d.

Common difference = $a_2-a_1$

According to question

$a_7 =a+6d-(i)$    (where d is given in the question)

Put the value of d in equation (i) to find a

$a_7=a+6\times-4=4$

$a-24=4$

$a=4+24$

$a=28$