Respuesta :

are you asking for the 9th term or the 10th term?

First difference in the sequence is:-

7  9  11  13  15  17

second difference =  2 so nth term contains n2

subtracting  n^2 from the sequence

7    14    23   34    47

1      4     9    16     25    

=  6   10  14  18 22  this is an AP with first term 6 and common diff = 4

so formula is    n^2 + ( 6 + 4(n - 1)

= n^2 + 4n + 2  answer