72-(63-8) and (72-63)-8

The Priority is always to parenthesis. It means that in both equations, begin by operating what's inside the parenthesis. Then Subtract what's left.

For the first one you get:




For the second one you get:




Which mean that The 2 equations are not equal, because 
Hope this Helps! :D

The third box is a function

9/12 is the answer because 3/4 times 3 each is 9/12