The answer for this question that needs an answer is n = 5

because 18(n-1) = 9(n+7) implies that 18n - 18 = 9n + 63 which implies that n =5 for the equation to hold true.

because 18(n-1) = 9(n+7) implies that 18n - 18 = 9n + 63 which implies that n =5 for the equation to hold true.