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Camaro'
01-05-2010, 10:10 PM
Well, i'm learning the whole , SIN COS TAN thing, and i get it for the most part, but for some reason, im confused on this one problem..

http://img705.imageshack.us/img705/9428/trig.png

YoHoJo
01-05-2010, 10:14 PM
i r stupod.

Method
01-05-2010, 10:14 PM
Presumably there's a right angle where side x and the side going across the top meet, so there's a total of 90 degrees being shared by those two angles. The second angle should have a measurement of 22 degrees. Since you have an opposite and adjacent angle, you can use tangent, so you'll set up your equation like this:

tan(22) = 20/x

which then simplifies to:

x = 20/tan22

which can be worked out on a calculator.


Any idea what rule your supposed to be using on this? Can you tell me some rules you learned recently? Maybe then I can help me.

It's just simple trigonometry? :confused:

bullzeye95
01-05-2010, 10:18 PM
Inside angle on the top is 22*.

tan(22) = 20 / x
0.40403 = 20 / x
0.40403x = 20
x = 49.502

EDIT: Waah, Method winz

Method
01-05-2010, 10:20 PM
He doesn't need to use the law of sines YoHoJo???

Camaro'
01-05-2010, 10:25 PM
Thanks for your guys help, i had no clue ...

Awkwardsaw
01-05-2010, 10:54 PM
what do you need trig for? basic algebra could have solved it using pythag. :D

e: nvm. 20 is an angle, not a side :duh:

bullzeye95
01-05-2010, 11:01 PM
e: nvm. 20 is an angle, not a side :duh:

No, 20 is a side :p

Camaro'
01-05-2010, 11:04 PM
Cause 22 is a angle..

Camaro'
01-06-2010, 07:59 PM
Ahh you guys ended up doing it wrong, oh well.. My teacher said

Since the top line and the bottom line of the triangle are parallel, and theres a transveral in the middle of them(making a Z) then the top degree is the EXACT same as the angle of the triangle(bottom left) so the bottom left would be 68 degrees, and then thats how i was supposed to solve :(.. Oh well, thanks anyway.

Brain
01-06-2010, 08:08 PM
well If I would have seen this you would have gotten the right answer :p
sorry, lol.

Camaro'
01-06-2010, 08:14 PM
well If I would have seen this you would have gotten the right answer :p
sorry, lol.

Lol of course, brain has a big brain:)

mastaraymond
01-06-2010, 08:48 PM
Ahh you guys ended up doing it wrong, oh well.. My teacher said

Since the top line and the bottom line of the triangle are parallel, and theres a transveral in the middle of them(making a Z) then the top degree is the EXACT same as the angle of the triangle(bottom left) so the bottom left would be 68 degrees, and then thats how i was supposed to solve :(.. Oh well, thanks anyway.
Well yes.. But the right top = 90 - 68 = 22 degrees. It really doesn't matter which corner you take ;)
Either
Tan(68) = X / 20
or
Tan(22) = 20 / x

Brain
01-06-2010, 08:52 PM
i didn't even read the thread, tangent works too as the people above explained.
weird...I hate it when teachers want it done a certain way and ignore right ways that are different...

Camaro'
01-06-2010, 10:32 PM
i didn't even read the thread, tangent works too as the people above explained.
weird...I hate it when teachers want it done a certain way and ignore right ways that are different...

Tell me about it..

mc_teo
01-07-2010, 01:01 PM
Meh, your diagram doesnt show they are parallel.

line A||B would have done...

Have have you ever considered it could be the teacher that was wrong?

Camaro'
01-08-2010, 01:10 AM
Meh, your diagram doesnt show they are parallel.

line A||B would have done...

Have have you ever considered it could be the teacher that was wrong?

My diagram isnt exactly parrallel because i used paint.