There is no doubt that the 3 PTRs are extremely useful when solving problems modeled on a right triangle. Unfortunately, the world does not consist only of right triangles…
As a matter of fact, right triangles end up being more of a rarity than commonplace. Does that mean when we come across a situation that can only be modeled with a non-right triangle that we abandon our pursuit?….
No Way!!!! There exists 2 Laws of Trigonometry that allow one to solve problems that involve non-right Triangles:
A triangle is uniquely determined by two angles and a particular side A C B c b a O1O1 O2O2
If a corresponding angle and side are known, they form an “opposing pair” A C B c b a O1O1 O2O2
The Sine Law can be used to determine an unknown side or angle given an “opposing pair” A C B c b a O1O1 O2O2