# How do non right angle triangles differ from right angle triangles

• March 4th 2013, 07:26 AM
uperkurk
How do non right angle triangles differ from right angle triangles
I'm trying to solve what seems to be a basic triangle question but I keep getting strange results.

http://i.imgur.com/3p9EFL3.png

So I did $x1 = \frac{8}{\tan 14} = 32$

Then I did $a1 = \frac{8}{32} = 14$

Subsequently $x2 = 32^2+8^2 = 1088 \sqrt{1088} = 33$

So now I can say angle $a2 = 152$

Making the final triangle look like this

http://i.imgur.com/rno7tGy.png

I don't think it is correct though, I'm trying to use SohCahToa to solve this problem :/ Please help
• March 4th 2013, 07:37 AM
Plato
Re: How do non right angle triangles differ from right angle triangles
Quote:

Originally Posted by uperkurk
I'm trying to solve what seems to be a basic triangle question but I keep getting strange results.
http://i.imgur.com/3p9EFL3.png

What are you asked to do?
What do you know about the unknowns in the figure?

And NO you cannot apply trigonometric function here unless there is much more information that you have given us.
• March 4th 2013, 07:44 AM
uperkurk
Re: How do non right angle triangles differ from right angle triangles
Sorry I should have been a little more descriptive, I have to figure out what the unknowns are, as in x1, x2, a1 and a2. I can easily do it if I make it a right angled triangle, but for some reason this irregular triangle follows different rules?
• March 4th 2013, 07:54 AM
Plato
Re: How do non right angle triangles differ from right angle triangles
Quote:

Originally Posted by uperkurk
Sorry I should have been a little more descriptive, I have to figure out what the unknowns are, as in x1, x2, a1 and a2. I can easily do it if I make it a right angled triangle, but for some reason this irregular triangle follows different rules?

Well, from what you posted it impossible to do that.
If we know that the triangle is isosceles, then that would help.
But as is, nothing.
• March 4th 2013, 08:27 AM
uperkurk
Re: How do non right angle triangles differ from right angle triangles
Well note to self, don't try to invent your own problems because they fail. Lol thanks anyway.
• March 4th 2013, 10:02 AM
HallsofIvy
Re: How do non right angle triangles differ from right angle triangles
You should remember, from geometry, such "congurence" theorems as "SSS", "SAS", "ASA", etc. Generally, if three parts of two triangles are the same then the two triangles are congruent. For others (and even three may not be enough- there is no "ASS" congruence theorem!) there may be non-congruent triangles with the same information, so you cannot calculate the size of the other parts from two parts of a triangle.