Question

13. As observed from the top of a 75 m high lighthouse from the sea-level, the angles of depression of two ships are 30° and 45°. If one ship is exactly behind the other on the same side of the lighthouse, find the distance between the two ships​

Answer 1

Answer:

(ii) Angles of depression of two ships from the top of the lighthouse are 30∘ and 45∘. 45 ∘ .

Answer 2

Answer:

Given that height of the lighthouse is 75 m

Hence, AD = 75 m

And angle of depression of first ship is 45°

So, 2PAC = 45°

And angle of depression of second ship is 30°

So, Z PAB = 30 °

We need to find distance between the two ships, i.e. BC

Now,

Lines PA & BD are parallel

And AB is the transversal

.. Z AND = Z PAB

So, 2 ABD = 30°

Similarly,

Line PA & BD are parallel

And AC is the transversal

.. Z AND = L PAC

So, Z ACD = 45°

(Alternate angles)

Since lighthouse is perpendicular to ground

Z ADB = 90°