Question

an aeroplane at an altitude of 200 metres observes the angle of depression of opposite points on the two banks of a river to be 45 and 60 . find the width of the river​

Answer 1

Step-by-step explanation:

I think, this is the answer.

Answer 2

Answer:

widht of river is 84.39 metres

Step-by-step explanation:

let us suppose that the height of aeroplane ia AB=200m

let us suppose that the widht of river is(y)m .

In triangle ADB

tan45 = 200/x

1= 200/x

x=200m

In triangle ACB

tan 60 =200/BC

root 3 =200/BC

BC=200/ROOT3

THEN ,

y=x-BC

y=200-200/root3

y= 200(1-1/root3)

so,

y=84.39metres