Answer:
x^2 - 16x + 64
Explanation:
(x-8)^2 = x^2 - 16x + 64
the way to slove squared expressions you will have to square the first term (it's x^2 in here)then multiply the first and second term and double it (x×8×2 = 16x) and lastly get the second term squared by multiplying it by itself (8×8 = 8^2 = 64)