Hm... I think 440 Square feet..?
3^x is raising 3 to an unknown number or variable, while x^3 is raising a variable to 3 (x*x*x)
The correct answer would be 3(7+1) because 7+1=8 and 8 times 3 equals 24. 24 divided by six is 4 plus 20 would also be 24.
Your answer is (z+1+w) (z+1-w)