| A | B |
|---|
| median | segment from the vertex to the midpoint of the opposite side |
| altitude | segment from a vertex that is perpendicular to the opposite side |
| angle bisector | segment that bisects the angle of a triangle |
| centroid | the point of concurrency for the medians of a triangle |
| circumcenter | point of concurrency for the perpendicular bisectors of a triangle |
| orthocenter | point of concurrency of the altitudes of a triangle |
| incenter | point of concurrency of the angle bisectors of a triangle |
| scalene | a triangle with no congruent sides |
| isosceles | a triangle with 2 congruent sides |
| equilateral | a triangle with 3 congruent sides |
| equiangular | a triangle with 3 congruent angles |
| CPCTC | corresponding parts of congruent triangles are congruent |
| concurrent lines | lines that intersect in one and only one point |
| congruent segments | segments that have the same measure |
| interior angle of a triangle | an angle formed by two sides of a triangle such that the angle is on the inside of the triangle |
| perimeter | the sum of the lengths of a shape's sides |
| acute triangle | a triangle in which all the angles are acute |
| obtuse triangle | a triangle which has one obtuse angle |
| right triangle | a triangle which has a right angle |
| SAS, ASA, SSS | three ways to prove two triangles congruent |
