Always follow the following order to simplify a equation.
B - Brackets, do all the maths contained in brackets first
O - Orders, square roots, powers and anything else not listed below are all done next
D - Division, do your divisions now
M - Multiplication
A - Addition
S - Subtraction
This is an order of mathemetical standard.
8-4=4, so we now have
Order (the square):
square of 4 is 16, giving
Multiply comes before add so we have:
Finally our addition and answer is