Answer:
A. 3791 ft.
Explanation:
I am assuming the distance walked = 1000 ft.
Consider the large triangle:
tan 25 = x / (1000 + y), where y is the length of the base of small triangle.
Now consider the small triangle(inside the large one):
tan 28 = x/y
From the last equation x = y tan28
So substituting for x in the first equation:
tan25 = y tan28 / (1000 + y)
1000tan25 + y tan 25 = y tan 28
y (tan28 - tan25) = 1000 tan25
y = 1000 tan25 / (tan28 - tan25)
= 7129.9 ft
So x = 7129.9 * tan 28
= 3791.04 ft.