Answer:
54 ~ see below for explanation 
Explanation:
you're going to replace n with the 6 since n= 6
so (8+3)6 
then you're going to add 8+3 in the parenthesis because of PEMDAS 
(9)6 
you're going to multiply 6 by 9 since 9 is in parenthesis (a number in parenthesis means multiply) 
then you get 54 so the answer would be 54.