Question

why 90- B..pls explain​

Answer 1

Answer:

Step-by-step explanation:

Let us assume the ∠Q = x.

ΔAOQ is a right angled triangle with right angle at A i.e. ∠A = 90°.

So sum of all the angles is equal to 180°.

90 + x + β = 180°

x = 180 - 90 - β = 90 - β.

Thus angle of depression at O is 90 - β.