MATH 2360Q Lecture 8: Section 3.5 and 3.6
Document Summary
Math 2360q lecture 8 - chapter 3. 5 and 3. 6. In this section we"ll see two important theorems and some applications. However, for the sake of time, we won"t prove these two theorems. Let a, b, and c be three noncollinear points. The triangle abc is the union of the three segments ab, bc, and ac. If abc is a triangle and d is a point in the interior of bac, then there is a point g such that g lies on both ad and bc. We already knew that a ray which starts between two rays always has to stay between those rays (by the ray theorem). The crossbar theorem tells us that this ray has to hit the other side of the triangle. The second important theorem involves supplementary angles. Two angles bac and edf are supplementary (or supplements) if ( bac) + ( edf) = 180 .
