EXPLAINED
First you use PEMDAS (parentheses, exponents, multiplication, division, addition, subtraction)
You then plug in for N, which is now
6+2-3×6÷9
After that you do -3×6 which is -18
Now the new equation is
6+2-18÷9
You then do -18÷9 which is -2
Equation
6+2-2
You then add 6+2 and thats 8, and then subtract 2 from it
THE ANSWER IS 6
