15. *Cho hình bình hành ABCD, Ab là góc nhọn, AC cắt BD tại O, DE ⊥ AB tại E, DF ⊥ BC tại F.
(a) Chứng minh rằng tam giác FOE cân
(b) Giả sử BAD [ = m. Tính EOF [theo m.

m a t h w a y. c o m

step-by-step explanation:

the given problem looks very confusing because of the

unnecessary symbols and repeated letters or words. but i believe the correct

given variables are:

c = the number of boxes of cookies that are bought

d = which represents the cost of the amount of box of

cookies bought

the two variables are related by the given equation:

d = 4 * c

we are to find for d when c = 12. we can solve for d by

simply plugging in the value of c in the equation, that is:

d = 4 * 12

d = 48