1. Points of Concurrency Where multiple lines, segments rays intersect, have specific properties

2. Angle Bisector Incenter is the point of concurrency This point is equidistant from all the sides of the triangle You can use this point as the center of the circle and a point on the each side of the triangle to construct an inscribe circle

3. Perpendicular Bisector Circumcenter – this is the point of concurrency This point is equidistant from all of the vertices If you use the circumcenter as the center of the circle and all the vertices as points on the circle you will construction a circumscribed circle about the triangle

4. Altitudes Orthocenter – where the three altitudes intersect

5. Medians Centriod – is the point of concurrency for the medians of a triangle This is the point of the center of gravity for the triangle, could balance the triangle at this point

6. HW Pg 181 1-4