The length of the shadow of a building is 100 meters as shown below.

what is the height of the building?

50 m
100 m
200 m
55 m

The solution to the problem is as follows:

Here you have to consider a triangle.

The height is 396 m.

The base is 332 m.

So cos(angle) = 332/396 = 0.838
 
Here we can say angle = inverse of cos(0.838).

So angle = 33 degree (approx).
 
Cos(33) = 0.838.

Find theta.

Do arctan 70/30.
 
arctan is the tan button to the negative 1 power (tan ^ -1).

It should be the same button as tan, just need to press shift/2nd.

I hope my answer has come to your help. God bless and have a nice day ahead!

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