Question

Ifthe number X+3,2X+1and X-7 are in A.P .findthe value of X

Answer 1

Answer:

a1 = x+3

a2 = 2x+1

a3 = x-7

d1 (common difference 1) = a2 - a1

                                          = 2x+1 - (x+3)

d2 (common difference 2) = a3 - a2

                                            = x-7 - (2x+1)

given : numbers x+3 , 2x+1 and x-7 are in A.P

so d1 = d2

2x+1 - x-3 = x-7 - 2x-1

x-2 = -x-8

2x = -6

x = -3

Explanation: