Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

Normal Size Small Size show me how

Normal Size Small Size show me how

# Geometry: Chapter 1

### 49097 - Introducing Geometry

Question | Answer |
---|---|

point | smallest building block of geometry; has no size and indicates location |

line | a building block of geometry; made up of points, has no thickness, goes on forever in two directions |

plane | a building block of geometry; made up of points, has no thickness, is a flat surface that goes on forever |

collinear | points on the same line |

coplanar | points on the same plane |

segment | part of a line that has two enpoints |

congruent | having the same shape, size, and measurement |

measure of segment | length: measured in inches, centimeters, feet, etc. |

endpoints | two points at the end of a segment; all other points are between and collinear with the endpoints |

congruent segments | segments with the same length; shown in a picture with tickmarks |

midpoint | point on a segment that is the same distance from both endpoints |

bisect | to divide in two congruent parts |

ray | part of a line with one endpoing and goes on forever in one direction |

angle | two rays with a common endpoint |

vertex | the common endpoint of two rays |

sides of an angle | rays that go on forever |

measure of an angle | smallest amount of rotation around the vertex from one ray to the other; measured in degrees; measured with a protractor |

congruent angles | angles with the same measure (use arcmarks in the picture!) |

angle bisector | divides an angle into two congruent parts |

counterexample | something that fits a definition but isn't what you intended |

right angle | an angle whose measure is 90 degrees |

acute angle | an angle whose measure is less than 90 but greater than 0 |

obtuse angle | an angle whose measure is greater than 90 but less than 180 |

vertical angle | formed by two intersecting lines, they share a vertex but not a side |

linear pair | two angles that share a vertex and a side and their non-common sides form a line |

complementary | two angles whose measures add up to 90 degrees |

supplementary | two angles whose measures add up to 180 degrees |

parallel | lines that will never intersect and are on the same plane |

skew | lines that will never intersect and are not on the same plane |

perpendicular | lines that intersect at a 90 degree angle |

polygon | a closed plane figure whose sides are segments that connect at their endpoints |

diagonal of a polygon | a segment that connects two non-consecutive vertices in a polygon |

equilateral | a polygon whose sides are all congruent |

equiangular | a polygon whose angles are all congruent |

regular | a polygon that is both equilateral and equiangular |

convex | a polygon with no external diagonals |

concave | a polygon with at least a part of a diagonal outside of the polygon |

right triangle | a triangle with one right angle |

acute triangle | a triangle with three acute angles |

obtuse triangle | a triangle with one obtuse angle |

equiangular triangle | a triangle with three congruent angles |

scalene triangle | a triangle with no congruent sides |

isosceles triangle | a triangle with at least two congruent sides |

equilateral triangle | a triangle with all three sides congruent |

Created by:
lbosel