Question

For what value of 'k' will k+9,2k-1 and 2k+7 are the consecutive term of an A.P. ?

Answer 1

Answer:

2k-1-(k+9)=2k+7-(2k-1)

2k-1-k-9=2k+7-2k-1

k-10=6

k=16

Answer 2

a1 = k + 9

a2 = 2k - 1

a3 = 2k + 7

For this terms to be in AP :-

a2 - a1 = a3 - a2

$2k - 1 - (k + 9) = 2k + 7 - (2k - 1) \\ \\ 2k - 1 - k - 9 = 2k + 7 - 2k + 1 \\ \\ k - 10 = 8 \\ \\ k = 8 + 10 \\ \\ k = 18$

Hope it helps.