The answer is 399
PEMDAS
First is parenthesis, 20 - 8 = 12
Then exponents, 4^3 = 64
Since the 12 is still in parenthesis, you multiply it by the 64 and you get 768.
Moving onto the D in PEMDAS, you have to divide the 768 by 2 and you get 384.
And finally, addition. 384 + 6 = 390 and 390 + 9 = 399.
