13 [ 36 / (25 - 16) + 9 ]....first we start with the inner parenthesis
13 [ 36 / 9 + 9] ...now we do inside the brackets...starting with division
13 [ 4 + 9 ]....continue finishing inside the brackets
13 [ 13 ] ....now just multiply
169 <===
u still have to use PEMDAS...but when u have parenthesis within brackets...start with the inner stuff, then work outwards...if that makes sense
