So i started this by using induction and used n=1 for my base case which i got 10<25 which is true. Then i assumed that 5^k+5<5(k+1) for all k elements of N and computed:

5(k+1)+5< 5^(k+1)+1

soo i tried to split the right side to (5^k)x(5^2) then i got stuck

Can anyone please help me ?