CollegeGeometry1.1

an angle whose measure is between 0° and 90°

a triangle whose three interior angles are all acute

two angles that have a common vertex and a common side between them

the line segment from the vertex of the cone perpendicular to the plane of the base

a line segment between and perpendicular to each of the two bases

a line segment drawn perpendicularly from a vertex to a nonadjacent side (known as the related base) of the parallelogram

a line segment drawn perpendicularlyfrom a vertex to the remaining parallel side

a line segment drawn perpendicularly from a vertex of the triangle to the opposite side of the triangle; the length of the altitude is the height of the triangle

the plane figure formed by two rays that share acommon endpoint

the side of the triangle whose length is unique; the side opposite the vertex

the two parallel sides of the trapezoid

a ray that separates the given angle into two smaller, congruent angles

the interior point of the circle whose distance from all points on the circle is the same

the common center of the inscribed and circumscribed circles of the regular polygon

the interior point of the sphere whose distance from all points on the sphere is the same

an angle whose vertex is at the center of the circle and whose sides are radii of the circle

an angle whose vertex is at the center of the regular polygon and whose sides are two consecutive radii of the polygon

the point of concurrence for the three medians of the triangle

any line segment that joins two points on the circle

acute angle formed by a horizontal ray and a ray determined by a downward (an upward) rotation

any line segment drawn from the center of the regular polygon perpendicular to one of its sides

the segment (part) of a circle determined by two points on the circle and all points between them

the measurement, in square units, of the amount of region within an enclosed plane figure

a line (or part of a line) added to a drawing tohelp complete a proof or solve a problem

a side (of a plane figure) or face (of a solid figure) to which an altitude is drawn

the two congruent angles of the isosceles triangle

the set of points in a plane that are at a fixed distance from a given point (the center of the circle) in the plane

the center of the circumscribed circle of a triangle; the point of concurrence for the perpendicular bisectors of the three sides of the triangle

the linear measure of the distance around a circle

a circle that contains all vertices of a polygon whose sides are chords of the circle

a polygon whose sides are all tangent to a circle in the interior of the polygon

points that lie on the same line

a line (or segment) that is tangent to more than one circle; can be a common external tangent or a common internal tangent

two angles whose sum of measures is 90°

a polygon in which at least one diagonal lies in the exterior of the polygon

two or more circles (spheres) that have the same center

the “then” clause of an “If, then” statement; the part of a theorem indicating the claim to be proved

three or more lines that contain the same point

refers to figures (such as angles) that can be made to coincide

relative to the statement “If P, then Q,” this statement has the form “If Q, then P”

a polygon in which all diagonals lie in the interior of the polygon

points that lie in the same plane

a theorem that follows from another theorem as a“by-product”; a theorem that is easily proved as the consequence of another theorem

in a right triangle, the ratio

in a right triangle, the ratio

in a right triangle, the ratio

a right square prism whose edges are congruent

a polygon that can be inscribed in a circle

the solid generated by all line segments parallel to the axis of the cylinder and which contain corresponding end points on the two congruent circular bases

a polygon with exactly 10 sides

a form of reasoning in which specific conclusions are reached through the use of established principles

the unit of measure that corresponds to of a complete revolution; used with angles and arcs

a line segment that joins two nonconsecutive vertices of a polygon

any line segment that joins two points on a circle (or sphere) and that also contains the center of the circle (or sphere)

a polygon that has exactly 12 sides

a polyhedron that has exactly12 faces that are congruent regular pentagons

any line segment that joins two consecutive vertices of the polyhedron (includes prisms and pyramids)

a type of polygon whose angles are congruent (equal)

a type of polygon whose sides are congruent(equal)

equations for which the solutions are the same

a proportion that has three or moremembers, such as

a ratio that compares three or more numbers,such as a:b:c

refers to all points that lie outside an enclosed(bounded) plane or solid figure

an angle formed by one side of the polygon and an extension of a second side that has a common endpoint with the first side

• the first and last terms of a proportion; in ,
• a and d are the extremes

any one of the polygons that lies in a plane determined by the vertices of the polyhedron; includes base(s) and lateral faces of prisms and pyramids

the repeated second and third terms of certain proportions; in ,

b is the geometric mean of a and c

the length of the altitude of a geometric figure

a polygon that has exactly seven sides

a polygon that has exactly six sides

a polyhedron that has six congruent square faces; also called a cube

the side of a right triangle that lies opposite the right angle

the “if” clause of an “If, then” statement; the part of a theorem providing the given information

a polyhedron with 20 congruent faces that are equilateral triangles

the center of the inscribed circle of a triangle; the point of concurrence for the three angle bisectors of the angles of the triangle

a form of reasoning in which a number of specific observations are used to draw a general conclusion

an angle whose vertex is on a circle and whose sides are chords of the circle

a circle that lies inside a polygon in such away that the sides of the polygon are tangents of the circle

a polygon whose vertices all lie on a circle in such a way that the sides of the polygon are chords of the circle

the arc (an arc) of a circle that is cut off in the interior of an angle (or related angle)

the points at which the graph of an equation intersects the axes

refers to all points that lie inside an enclosed (bounded) plane or solid figure

any angle formed by two consecutive sides of the polygon in such a way that the angle lies in the interior of the polygon