<PRE><B>Question 882802</B>
Find the angles in the triangle when a = 13, b = 12, and c = 11. Round your answers to the nearest tenth.
------------
Use the Cosine Law
{{{c^2 = a^2 + b^2 - 2ab*cos(C)}}}  Angle C is opposite side c
{{{11^2 = 13^2 + 12^2 - 2*13*12*cos(C)}}}
cos(C) = 192/312 = 8/13
C =~ 52.02 degs
--------
You can get another angle the same way, or use the Law of Sines
---
c/cos(C) = b/cos(B) = a/cos(A)
-----
After you find a 2nd angle, the 3rd is 180 - sum of the other 2.
</PRE>