Prove the divisibility of the following numbers:51^7-51^6 by 25

Hello from MrBillDoesMath! Answer: See Discussion belowDiscussion: 51^7 - 51^6  =                            => as 51^7 = 51^6 * 5151^6*51 - 51^6 =                      => factor 51^6 form each terms51^6(51 - 1)      =                       => as 51 -1 - 5051^6* 50          =                      => as 50 - 2 * 2551^6 ( 25*2)so the original expression is divisible by 25 Thank you, MrB