Given the first three terms of the arithmetic sequence

(2p-3) ; (p-5);(2p+7)

find the value of p

4 answers

by definition of AP
p-5 - (2p-3) = 2p+7 - (p-5)
p - 5 - 2p + 3 = 2p + 7 - p + 5

I will let you solve this for p, very straight forward.
Struggling to find the answer
from:
p - 5 - 2p + 3 = 2p + 7 - p + 5
-p - 2 = p + 12
-2p = 14
p = -7
you forget your Algebra I?
p - 5 - 2p + 3 = 2p + 7 - p + 5
-p-2 = p+12
-2p = 14
p = -7