click below
click below
Normal Size Small Size show me how
Triangle Properties
| Question | Answer |
|---|---|
| Acute Triangles | All angles are less than 90 degrees |
| Right Triangles | One angle is 90 degrees, the other two angles are less than 90 degrees. |
| Obtuse Triangles | One angle is greater than 90 degrees, the other two angles are less than 90 degrees. |
| Scalene Triangles | All of the sides are different measures. |
| Isosceles Triangles | Two sides are congruent. |
| Equilateral Triangles | All sides are congruent. |
| Triangle-Angle-Sum Theorem | All three interior angles add up to 180 degrees. |
| Exterior Angle Theorem | The measure of an exterior angle is the sum of the two interior angles. |
| Isosceles Triangle Theorem | Two angles of a triangle are congruent if and only if two sides of a triangle are congruent. |
| Altitude | The special segment that connects a vertex to the opposite side and is perpendicular to that side. |
| Angle Bisector | The special segment that bisects one angle of the triangle. |
| Centroid | The point of concurrency that is formed by the three medians of the triangle and is the center of gravity. |
| Circumcenter | The point of concurrency that is formed by the perpendicular bisectors. |
| Euler Line | The special line in a triangle that includes three points of concurrency: circumcenter, centroid, and orthocenter. |
| Incenter | The point of concurrency that is formed by the angle bisectors. |
| Median | The special segment whose endpoints are a vertex and the midpoint of the opposite side. |
| Midsegment | The special segment that joins the midpoints of two sides of a triangle. |
| Orthocenter | The point of concurrency where the three altitudes of the triangle meet. |
| Perpendicular Bisector | The special segment that bisects the side of the triangle and is perpendicular to that side. |
| Triangle Inequality Theorem | Two sum of two sides of a triangle will be greater than the third side. |