Question

For what value of k will k+9 2k-1 and 2k+7 are in ap

Answer 1

Given:

• k+9 , 2k-1 and 2k+7 are in AP .

To find :

•The value of k.

Solution :

• As we know that , In AP common difference is same .

• b-a= c-b

=> 2b= a + c .

Here ,

• a = k+9

•b= 2k-1

•c= 2k+7 .

$\implies \: 2b = a + c \\ \\ \implies \: 2(2k - 1) = k + 9 + 2k + 7 \\ \\ \implies \: 4k - 2 = 3k + 16 \\ \\ \implies4k - 3k = 16 + 2 \\ \\ \implies \: k = 18$

Hence, The value of K is 18