Question

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On walking 20m towards the foot of a house the angle of elevation changes from 30° to 45° .
Find the height of the house .​

Answer 1

Given

Angle D=30°

And

Angle C=45°

As shown in the figure:-

MN||DC

Hence

Angle MAC = Angle ACB

And

Angle NAD =Angle ADB

Acc to que

Tan C=AB/BC

Tan45°=20/BC

BC=20.

Again for D:-

Tan D= AB/BD

Tan 30° = 20/BD

BD=20/root 3

Total distance = BC+BD

= (20+20root 3)m

20(1+root 3) m

Hope it HELPS you ☺☺

Answer 2

Answer:

20(1+root3)m is your answer....