| A | B |
|---|
| bisect | divides into two equal pieces |
| midsegment | connects midpoints of sides |
| equidistant | same distance |
| concurrent | 3 or more segments intersecting |
| circumcenter | equidistant from vertices of triangle |
| incenter | equidistant from sides of triangle |
| centroid | 2/3 from vertex, 1/3 from side |
| median | point of concurrency is centroid |
| altitude | height |
| angle bisector | point of concurrency is incenter |
| vertex | point of intersection of the two rays of an angle |
| Hinge Theorem | All else being equal the longer side is across from the larger angle |
| Converse of the Hinge Theorem | All else being equal, the larger angle is across from the longer side |
| Midsegment Theorem | Parallel to side not intersected and 1/2 as long |
| orthocenter | concurrency of altitudes |
| Triangle Inequality Theorem | the sum of the lengths of any two sides must be > than the third side |
| Indirect Proof | Prove that it can't be false so it must be true |
| Triangle Sum Theorem | The interior angles sum to 180 |
| Exterior Angle Theorem | Equals sum of the two remote interior angles |
| perpendicular bisector | point of concurrency is circumcenter |
