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4 votes
A building that is 100 for tall casts a shadow that makes a 30 degree angle. Approximately how long in feet is the shadow across the ground?

User Galenus
by
5.6k points

2 Answers

7 votes

Hello!

The answer is:

The shadow is 173.20 feet

Why?

To solve the problem, we need to calculate the projection of the building's shadow over the ground.

We already know the height of the building (100 feet), also, we know the angle of elevation (30°), so, we can use the following formula to calculate it:


Tan(\alpha)=(y)/(x)=(height)/(x)\\\\x=(height)/(Tan(\alpha) )

Now, substituting the given information and calculating, we have:


x=(height)/(Tan(\alpha) )


x=(100feet)/(Tan(30\°) )=173.20feet

Have a nice day!

User Qaiser Mehmood
by
5.2k points
2 votes

Answer: 173.20 ft

Explanation:

Observe the attached image. To know how long the shadow is, we must find the length of the adjacent side in the triangle shown. Where the opposite side represents the height of the building

By definition, the function
tan (x) is defined as


tan(x) = (opposite)/(adjacent)

So


opposite = 100\ feet\\x=30\°


adjacent = l

Then


tan(30\°) = (100)/(l)


l = (100)/(tan(30\°))


l = 173.20\ ft

A building that is 100 for tall casts a shadow that makes a 30 degree angle. Approximately-example-1
User Dennis Golomazov
by
5.3k points
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