# Geometry Final

 The flashcards below were created by user Luna0596 on FreezingBlue Flashcards. Perpendicular Bisector A segment, ray, line, or plane that is perpendicular to a segment at its midpoint. Equidistant A point that is the same distance from two or more other points. Distance from a point to a line. The length of the perpendicular segment from the point to the line. Equidistant from the two lines. A point that is the same distance from one line as it is from another. Perpendicular Bisector of a triangle A line, ray, or segment that is perpendicular to a side of the triangle at the midpoint of the side. Concurrent Lines When three or more lines, rays, or segments intersect in the same point. Point of Concurrency The point of intersection of concurrent lines. Circumcenter The point of concurrecy of the perpendicular bisectors of a triangle. Can lie inside, on, or outside of the triangle. Angle bisector of a triangle A bisector of an angle of the triangle. Incenter of the Triangle The point of concurrency of the angle bisectors. Median of a Triangle A segment whose endpoints are a vertex of the triangle and the midpoint of the opposite side. Centroid of the Triangle The point of concurrency for the medians of a triangle. Altitude of a Triangle The perpendicular segment from a vertex to the opposite side or to the line that contains the opposite side. Orthocenter of the Triangle The point of concurrency of the altitudes of a triangle. Can lie inside, outside, or on the triangle. Midsegment of a Triangle A segment that connects the midpoints of two sides of a triangle. Polygon A plane figure that is formed by three or more segments called sides (no two sides with a commmon endpoint are collinear), and the sides intersect exactly two other sides. Vertex The endpoint of a side of a polygon. Convex A polygon where no line that contains a side of the polygon contains a point in the interior of the polygon. Convex A polygon that contains a side with a point in the interior of the polygon. Equilateral All of the sides of a polygon are congruent. Equiangular All the interior angles are congruent. Regular All of the interior angles of a polygon are congruent and all of the angles are congruent. Paralellogram A quadrilateral with both pairs of opposite sides parallel. Rhombus A parallelogram with four congruent sides. Rectangle A parallelogram with four right angles. Square A parallelogram with four congruent sides and four right angles. Trapezoid A quadrilateral with exactly one pair of parallel sides. Isosceles Trapezoid A trapezoid with congruent legs. Kite A quadrilateral that has two pairs of consecutive congruent sides, but opposite sides are not congruent. Image The figure as a result of a reflection, rotation, or translation. Preimage The original figure before a transformation. Transformation An operation that maps, or moves, the preimage onto the image. Isometry A transformation that preserves lengths. Also preserve angle measures, parallel lines, and distances between points. Also called rigid transformations. Reflection A type of transformation that uses a line like a mirror, with an image reflected over the line. Line of Symmetry A figure in a plane has a line of symmetry if the figure can be mapped onto itself by a reflection in the line. Rotation A transformation in which a figure is turned about a fixed point. Center of Rotation The fixed point about which a figure is turned for a transformation. Angle of Rotation The angle formed from rays drawn from the center of rotation to a point and its image. Rotational Symmetry When a figure can be mapped onto itself by a rotation of 180 degrees or less. Translation A transformation that maps every two points in the plane so that the result is an isometry. Vector A quantity that has both direction and magnitude (size) and is represented by an arrow drawn between two points. Initial Point Starting point of a vector Terminal Point Ending point of a vector, prime Component Form Combines the horizontal and vertical components <5,3> Glide Reflection A transformation in which every point is mapped on to the image by a translation, and then a reflection. Composition Two or more tranformations are combined to produce a single transformation. Similar Polygons When there is a correspondence between two polygons such that their corresponding angles are congruent and the lengths of corresponding sides are proportional. Scale factor The ratio of the lengths of two corresponding sides of similar polygons. Dilation Dilation is a similarity transformation in which a figure is enlarged or reduced using a scale factor ≠ 0, without altering the center. Reduction A dilation where the scale factor is less than one but greater than zero. Enlargment A dilation where the scale factor is greater than one. Trigonometric Ratio A ratio of the lengths of two sides of a right triangle. Radius A segment whose endpoints are the center of the circle and a point on the circle. Diameter A chord that passes through the center of the circle. Chord A segment whose endpoints are on the circle. Secant A line that intersects a circle in two points. Tangent A line in the plane of a circle that intersects the circle in exactly one point. Tangent Circles Coplanar circles that intersect at one point. Concentric Coplanar circles that have a common center. Point of Tangency A point at which a tangent line intersects the circle to which it is tangent. Central Angle An angle whose vertex is the center of a circle. Minor Arc A central angle with a measure of less than 180 degrees. Major Arc A central arc whose measure is greater than 180 degrees. Semicircle The endpoints of an arc are the endpoints of a diameter. Inscribed Angle An angle whose vertex is on a circle adn whose sides contain chords of the circle. Intercepted Arc The arc that lies in the interior of an inscribed angle and has endpoints on the angle. AuthorLuna0596 ID155326 Card SetGeometry Final Descriptiongeometry vocabulary Updated2012-05-23T01:59:39Z Show Answers