Answer:
524.5 feet
Step-by-step explanation:
Given: Height of cliff= 200 ft
Angle of depression at sail boat is 42°
Angle of depression at yacht is 15°
Lets assume distance sailboat from the bottom of cliff is "
"
And assume distance yacht from the bottom of cliff is "
"
Now using tangent rule to solve it.
we know, 
Distance sailboat from the bottom of cliff; 
Using trignometry table to know the value of tan 42°
⇒
cross multiplying both side.
⇒ 
∴ Distance sailboat from the bottom of cliff (
= 222 feet
Distance yatch from the bottom of cliff; 
Using trignometry table to know the value of tan 15°
⇒
cross multiplying both side.
⇒ 
∴Distance yacht from the bottom of cliff
= 746.5 feet.
Next, finding the distance between sailboat and yacht.
Distance between sailboat and yacht = 
⇒ Distance between sailboat and yacht= 
∴ Distance between sailboat and yacht is 524.5 feet.