| A | B |
|---|
| acute angle | an angle with a measure less than 90 degrees |
| acute triangle | A triangle with no angle measuring 90 degrees or more |
| angle | Two rays that share an endpoint |
| area | The measure, in square units, of the interior region of a 2-dimension fiqure or the surface of a 3-dimensional figure |
| bisect | to cut or divide into two equal parts |
| circle | A closed curve that all it's piont on the same plane and the same distance from a fixed point |
| circumference | The boundry line, or perimeter, of a circle |
| complementry angles | two angles that have measures with a sum of 90 degrees |
| degree | A unit of angle measure. 1 degree equals the central angle of a circle formed by rays that cut 1/360 of its circumference |
| height | the perpendicular distance from a vertexto the opposite side of a plane figure |
| hexagon | A polygon with six sides |
| intersect | to meet or cross |
| isosceles triangle | A triangle that has at least two congruent sides |
| length | The distances along a line or figure from one point to another |
| line | An infinite set of points that form a straight path extending in 2 directions |
| line segment | A part of a line defined by two end points |
| obtuse angle | An angle greater then 90 degrees and less than 180 degrees |
| obtuse triangle | A triangle whose largest angle measure greater than 90 degrees and less than 180 degrees |
| octagon | A polygon with eight sides |
| parallel | Always the same distance apart |
| parallelogram | A quadrilateral with two pairs of parallel and congruent sides |
| pentagon | A polygon that has five sides |
| perimeter | The distance around a figure |
| perpendicular | Forming right angles |
| pi | The ratio of the circumference of any circle to its diameter, approximatgely equal to 3.14 |
| plane | A flat surface that extends infinitely in all directions |
| plane figure | Any 2-dimensional figure |
| point | An exact position in space |
| polygon | A closed figure formed from line segments that meet only at their endpoints |
| ray | A part of a line that has one endpoint and extends infinitely in one direction |
| rectangle | A quadrilateral with two pairs of congruent, parallel sides and four right angles |
| rhombus | A parallelogram with all four sides equal in length |
| right angle | An angle that measures exactly 90 degrees |
| right triangle | A triangle that has one 90 degree angle |
| scalene triangle | A triangle that has no congruent sides |
| semicircle | An arc that is exactly half of a circle. A diameter intersects a circle at the endpoints of two semicircles |
| square | A parallelogram with four congruent sides and four right angles. |
| straight angle | An angle with a measure of 180 degrees. |
| supplementary angles | Two angles that have measures whose sum is 180 degrees. |
| trapazoid | A quadrilateral with exactly one pair of parallel sides. |
| triangle | A three-sided polygon. |
| vertex | The point at which two line segments, lines,or rays meet to form an angle. |
| width | One dimension of a 2-dimensional or 3-dimensional figure. |
| diameter | chord passing through the center of a circle |
| decagon | a polygon with ten sides |
