Hi, How do I find the height of the triangle , the triangle is set

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Pin Head
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Hi,
How do I find the height of the triangle , the triangle is set at 30 degrees and the length is 5 meters any help would be appreciated.
 
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Pin Head said:
Hi,
How do I find the height of the triangle , the triangle is set at 30 degrees and the length is 5 meters any help would be appreciated.

Can you tell us what you know about trig so far? What learning resources are you using?

This page may be helpful:

http://en.wikipedia.org/wiki/Trigonometry

.
 


Pin Head said:
Hi,
I' ve been learning trig using Khan accademy

Was the wikipedia page helpful? It answers your original question...
 


Pin Head said:
Hi,
I' ve been learning trig using Khan accademy

Wow, that's a crazy website! So much to learn! :biggrin:
 


Okay I check out the wiki page and I am still a little confused ,This is what I'm thinking, is that I have to use tan = opposite / adjacent because I know the adjacent is 5 meters and I'm figuring that opposite is 90 degrees is this right
 


Pin Head said:
Okay I check out the wiki page and I am still a little confused ,This is what I'm thinking, is that I have to use tan = opposite / adjacent because I know the adjacent is 5 meters and I'm figuring that opposite is 90 degrees is this right

You are close. The tan(theta) = opposite side from the angle / adjacent side to the angle.

Your angle is the 30 degrees, and the 5 meter side is adjacent to it. So you have:

tan (30 degrees) = opposite side / 5m

Do you have a calculator that has tan(theta) on it? If so, you should be able to figure out the answer now. Post it for us to check...
 


Pin Head said:
Okay I check out the wiki page and I am still a little confused ,This is what I'm thinking, is that I have to use tan = opposite / adjacent because I know the adjacent is 5 meters and I'm figuring that opposite is 90 degrees is this right

That's the right function to use, but the opposite is the opposite side, the height you want to find.

Let h be the length of the opposite side. Now write an equation that involves the tangent of the angle you know, and the two sides, then solve for the unknown side h.
 


Hi,
So I use my calculator I keyed tan 30 / 5 and got 0.115470053 did I calculate this right or was I supposed to put tan 30 * 5 = 2.886751346 0r have I got this completely totally wrong?
 


That value is way off.

Before doing anything with your calculator, write down the equation that I suggested. Then solve for the unknown, and then use your calculator. (Make sure it is in degree mode.)