Across
- 2. - A line segment where two faces of a polyhedron meet.
- 4. polygon - Intuitively speaking, curved away from the eye. A concave figure is a set of points some of whose chords include points that are in the set.
- 7. - A set of logical arguments used to deduce or prove a mathematical theorem from a set of axioms.
- 9. - A perfect round ball. A sphere is a closed solid bounded by a surface on which all points are equidistant from a central point called the center.
- 12. - A straight line or a plane that divides a line, a plane, an angle, or a shape into two equal parts.
- 15. - A point at which the two rays of an angle meet or the intersection point of two sides of a plane figure.
- 16. - The surface included within a closed figure, measured by the number of square units needed to cover the surface.
- 18. - The boundary line of a circle or the length of such a boundary line.
- 19. - A closed plane figure bounded by at least three line segments.
- 20. - Two lines that intersect at right angles.
- 23. - Having one thing on either side of it. 2 is between 1 and 3.
- 24. - Planar figures or solid shapes that have the same shape and size.
- 27. - A unit of measure used to measure the magnitude of an angle, equal in magnitude to 1/360 of a complete revolution.
- 28. pair - Two angles that are adjacent (share a leg) and supplementary(add up to 180°)
- 29. - The distance from the center of a circle to any point on its circumference.
- 30. angles - Two angles that share the same vertex and have one side in common between them.
- 31. - Two angles that add up to 180°.
- 33. angle - An angle with a measure between 0° and 90°.
- 34. - Points or lines that all lie in the same plane.
- 36. - The side opposite the right angle in a right triangle.
- 39. angle - An angle that measures 90° or /2 radians. It is the angle between two perpendicular lines such as the corner of a square or two perpendicular planes such as the wall and the ground.
- 40. - A line segment that passes through the center of a circle and has its two endpoints on the circle. It also represents the length of such a line segment.
- 42. segment - Part of a line between two points called endpoints.
- 43. - A flat surface that can extend forever in length and width but has no thickness. The surface of a calm sea and a flat valley are all physical models of a plane.
Down
- 1. - A general conclusion proposed to be proved upon the basis of certain given hypotheses or assumptions; or, a general conclusion that has been proved, e.g., Pythagorean Theorem, Binomial Theorem, Fundamental Theorem of Algebra, etc.
- 3. rays - Two rays with a common endpoint that point in opposite directions and form a straight line.
- 4. - A can-shaped solid figure.
- 5. - Often referred to as the right cone. A cone is a solid formed by rotating a right triangle around one of its legs.
- 6. - The length of the boundary around a shape or a figure.
- 7. - A geometric object that has no dimension and is used to indicate a location.
- 8. - A planar surface of a solid figure.
- 10. - A space figure with two parallel polygonal bases that are the same shape and the same size.
- 11. term - In geometry, definitions are formed using known words or terms to describe a new word. There are three words in geometry that are not formally defined. These three undefined terms are point, line and plane.
- 13. angle - An angle that is between 90° and 180°.
- 14. - Also called half-line. It is a straight line that extends from a point.
- 17. - The figure formed by two rays from the same initial point. The two rays are called the sides of the angle and the initial point is called the vertex of the angle. The symbol for angle is
- 18. - A pair of angles that add up to 90°. As shown, 1 is the complementary angle of 2.
- 19. - to ask, demand, or claim.
- 21. - A pair of numbers that describe the position of a point on a coordinate plane by using the horizontal and vertical distances from the two reference axes.
- 22. - Lying on the same straight line.
- 25. angles - The pair of angles opposite each other formed by two intersecting lines.
- 26. - An additional geometric figure that is constructed to assist in solving a problem or producing a proof.
- 32. - A solid bounded by at least four polygonal faces. The pairs of faces meet along their edges. Three or more edges meet in each vertex. A diagonal of a polyhedron is a line segment joining two vertices that are not in the same face.
- 34. polygon - Intuitively speaking, curved outward or toward the eye. A convex curve is a set of points any of whose chords do not include any point that is not in the set.
- 35. - A polyhedron whose one face is a polygon and the other faces are triangles with one common vertex. This polygon is the base of the pyramid. The other triangles are the lateral faces. The common vertex of these lateral faces is the vertex of the pyramid. The segment from the vertex perpendicular to the base is called the altitude of the pyramid. The length of the altitude is called the height of the pyramid. The intersections of the adjacent lateral faces are called the lateral edges of the pyramid.
- 37. - Two or more straight coplanar lines that do not intersect.
- 38. - Also called non-coplanar lines. They are straight lines that are neither parallel, nor intersecting. They lie in different planes.
- 41. - The point on a line segment that divides the given line segment into two congruent parts.