On the first day she wen from 934 - 16 pages. Then everyday after that means it would x - 16 pages = PL (PL = Pages Left) so the answer is x - 16 = PL
Unfortunately your response would only be true if CD was perpendicular to AB. However we don't know if CD is perpendicular or not. So we don't have enough information. The actual answer is choice E) None of these.
Answer:
30
Step-by-step explanation:
2/9 and 5/6 have a lcm of 30.
The angle does not matter. Think of it as finding the other side to a triangle. Use

a=39 (line AB)
b=b (the leg we need to find)
c=89 (line BD)


(subtract the 1521 from both sides)

(square root both sides)

b = 80
AD=80