Abstract. This paper derives the Law of Cosines, Law of Sines, and the
Pythagorean Theorem for triangles in Hyperbolic Geometry. The Poincar´e
model for Hyperbolic Geometry is used. In order to accomplish this the paper
reviews Inversion in Hyperbolic Geometry, Radical Axes and Powers of circles
and expressions for hyperbolic cosine, hyperbolic sine, and hyperbolic tangent.
A brief history of the development of Non-Euclidean Geometry is also given
in order to understand the importance of Euclid’s Parallel Postulate and how
changing it results in different geometries.