If the first three terms of an arithmetic progression are (x+3). (3x-10) and (2x+12), find x.

 (3x-10) - (x+3) =  (2x+12) -  (3x-10), solve for x

 

 x=35/3 and the common difference =31/3. So:

 

First term =44 / 3

2nd term  = 25

3rd term   =106/3