N( n + 14 ) - ( n - 6 )( n + 4 ) = n^2 + 14n - ( n^2 + 4n - 6n - 24 ) = n^2 + 14n - n^2 + 2n + 24 = 16n + 24 = 8•( 2n + 3 )
N( n + 14 ) - ( n - 6 )( n + 4 ) = n^2 + 14n - ( n^2 + 4n - 6n - 24 ) = n^2 + 14n - n^2 + 2n + 24 = 16n + 24 = 8•( 2n + 3 )