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#### .dp-BarackObama

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1) You're standing 10 feet away from a building and looking at the top of the building where your eyes make a 60-degree angle with a horizontal line( angle of elevation). accurate to 1 decimal point, what is the total height of the building if you are 6 feet tall?

I can't even begin to think where to start. Help plz. Rep+

#### GingerJohn

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Right, start by drawing it out.

Hb = Height of the building

So what you have now is a triangle between the top of the building, your eye and 6' up the building.

Using trigonometry we can calculate the length of the other side. The equations you need are:

Sinθ=opposite / hypotenuse

For right angled triangles.

The adjacent refers to the length of the side next to the angle, opposite to the length of the side opposite the angle. The hypotenuse is the long length.

We know the length adjacent to the angle, 10'
We know the angle, 60Â°
We want to know the length opposite (Hb-6')

So we can use Tanθ = opposite / adjacent

Rearranged gives opposite = adjacent * Tanθ

This will give the vertical height from your eye to the top of the building. As you are 6' tall, you need to add the 6'.

Do this and post back with your answer. I will tell you if it right.

#### GingerJohn

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Did you get anywhere with this?

Let me know if there is any more help I can give you.

#### .dp-BarackObama

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Sorry I was working on some other school work, and took a break. Once i get back to it i'll post up what I have done. I'll get to it a little bit later tonight!

#### kennh

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If you are still stuck, here are a few pointers.

Its a 60' angle. This means that the other angles are 30 and 90. If you have learned about the special triangles, the short side is 1, the hypotenuse is 2x the short side and the other side is root3x the short side.

So since the short side in this case is the 10, we times 10 by root3 giving us 17.3. Then we add the height and get 23.3

#### .dp-BarackObama

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Finally got around to working my math. Have a test tomorrow. Hopefully it all goes well. I foresee me failing. Horribly. I figured out the problem and am doing good so far. I hope! haha.

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