Square | | a circle drawn around a polygon so that each vertex of the polygon lies on the circle |

Radius | | an angle with measure of 180 degrees (2 wds) |

Obtuse triangle | | an angle with measure of 90 degrees (2 wds) |

Cube | | a rectangular solid with square faces |

Scalene | | a segment joining two non-consecutive vertices of a polygon |

Equilateral | | any perpendicular segment connecting a vertex to an opposite side |

Right angle | | two angles in a plane that have a common vertex and a common side but no common interior points (2 wds) |

Rhombus | | the set of all points in space that are a given distance from a given point |

Hexagon | | a quadrilateral with exactly one pair of parallel sides |

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

Supplementary | | a segment whose endpoints lie on a circle |

Pentagon | | two triangles with sides of equal length and angles of equal measure (2 wds) |

Vertical angles | | a line, segment or ray that intersects a segment or angle and forms two congruent segments or angles |

Sphere | | an arc of a circle cut off by the diameter |

Transversal | | the figure formed by three segments joining noncollinear points |

Complementary | | two points on a line and all the points between them |

Segment | | an angle with measure between 90 and 180 degrees (2 wds) |

Chord | | in a right triangle a side adjacent to the right angle |

Perpendicular lines | | segments that have equal length (2 wds) |

Diameter | | an equation stating that two ratios are equal |

Secant | | an angle formed by two radii drawn to consecutive vertices (2 wds) |

Postulate | | the angle formed when one side of a polygon is extended (2 wds) |

Acute | | a chord that contains the center of a circle |

Hypotenuse | | a statement that can be proved |

Circumscribed | | a quadrilateral with four congruent sides |

Adjacent angles | | points all in one plane |

Parallel | | points all in one line |

Semicircle | | the distance from the center of a circle to any of its points |

Midpoint | | a 4-sided polygon |

Straight angle | | a quadrilateral with four right angles |

Similar | | a triangle with one obtuse angle (2 wds) |

Trapezoid | | two lines that intersect to form right angles (2 wds) |

Rectangle | | a 6-sided polygon |

Parallelogram | | the point that divides the segment into two congruent segments |

Leg | | two angles whose sides form two pairs of opposite rays (2 wds) |

Quadrilateral | | a polygon that is both equiangular and equilateral |

Collinear | | a triangle with no sides congruent |

Median | | a segment from the vertex to the midpoint of the opposite side |

Coplanar | | a quadrilateral with four right angles and four congruent sides |

Central angle | | a triangle with one right angle (2 wds) |

Tangent | | lines that are not coplanar |

Regular | | a triangle with all sides congruent |

Polygon | | a line in the plane that intersects a circle in exactly one point |

Congruent segments | | a line that contains a chord |

Exterior angle | | a triangle with three acute angles |

Skew | | in a right triangle the side opposite the right angle |

Congruent triangles | | a figure formed by two rays that have the same endpoint |

Triangle | | a quadrilateral with both pairs of opposite sides parallel |

Obtuse angle | | two angles whose measures have the sum 180 degrees |

Altitude | | a 5-sided polygon |

Bisector | | a plane figure formed by coplanar segments such that (1) each segment intersects exactly two other segments; and (2) no two segments with a common endpoint are collinear |

Proportion | | coplanar lines that do not intersect |

Diagonal | | two angles whose measures have the sum of 90 degrees |

Isosceles | | two triangles with congruent angles and corresponding sides in proportion |

Right triangle | | a line that intersects two or more coplanar lines in different points |

Angle | | a statement that is accepted without proof |