Do the problem in the parentheses first 7+2=9 bring down the rest of the problem 4-9 ÷3 Divide 9 by 3= 3 bring down the 4 and subtraction sign 4-3=1 1 is your final answer
Square root acts like a variable, so since there are 12 edges you want to distribute one length of an edge by 12. in the end youll get 144 + 120 square root 6