To solve this problem, we can use the tan function to find
for the distances covered.
tan θ = o / a
Where,
θ = angle = 90° - angle of depression
o = side opposite to the angle = distance of boat from
lighthouse
a = side adjacent to the angle = height of lighthouse = 200
ft
When the angle of depression is 16°18', the initial distance
from the lighthouse is:
o = 200 tan (90° - 16°18')
o = 683.95 ft
When the angle of depression is 48°51', the final distance
from the lighthouse is:
o = 200 tan (90° - 48°51')
o = 174.78 ft
Therefore the total distance the boat travelled is:
d = 683.95 ft - 174.78 ft
<span>d = 509.17
ft</span>
