| A | B |
|---|
| Acute angle | An angle of measure less than 90º, but more than 0°. |
| Alternate Exterior Angles | Angles on opposite sides of a transversal and outside the lines crossed by the transversal. |
| Alternate Interior Angles | Two nonadjacent angles on opposite sides of a transversal that are inside the lines crossed by the transversal. |
| Angle Bisector | A line or ray that divides an angle in half |
| Base Angles | The angles opposite the two equal sides in an isosceles triangles. A pair of angles that share a base as a common side in a trapezoid. |
| Complementary Angles | Two angles whose measures have a sum of 90º. |
| Congruent Triangles (SSS,SAS,ASA,AAS) | Triangles that have the same shape and size |
| Convex Polygons | A polygon in which the measure of each angle is less than 180º |
| Corresponding Angles | Angles that are located in similar places along a transversal that intersects two lines; also, angles from congruent or similar figures in corresponding positions. |
| Exterior Angle | An angle formed by one side of a polygon and the extension of an adjacent side |
| Interior Angle | The angle that open toward the inside of the polygon |
| Isosceles Triangle | A triangle with two sides of equal length |
| Obtuse Angle | An angle of measure greater than 90º and less than 180°. |
| Parallel Lines | Straight lines in a plane that never intersect, no matter how far they are extended. |
| Reflex Angle | An angle of measure greater than 180º and less than 360º. |
| Scaling Factor | The ratio of the lengths of corresponding sides of two similar figures. |
| Similar | Two objects such that the distance between any two points of one object is a particular constant times the distance between the corresponding points of the other object. |
| Straight Anlge | An angle of measure 180º. |
| Supplementary Angles | Two angles whose measures have a sum of 180º. |
| Transversal | A straight line that intersects two or more other coplanar straight lines at distinct points. |
| Vertical Angles | Congruent angles that form opposite each other when two lines intersect. |
