Interactive Geometry Glossary

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 3-D figure 45-45-90 triangle Acute angle, Acute triangle Adjacent angles Adjacent side Algorithm Alternate exterior angles Alternate interior angles Altitude Altitude of a triangle Ambiguous Analytic geometry Angle Angle bisector Angle measure between a line and a plane Angle side Angle-angle-angle (AAA) similarity Antecedent Arc Arc length Area ASA Automatic drawer Axiom Axis     Base Base (base side) of a trapezoid Base (base side) of a triangle Biconditional Bilateral symmetry Box Capacity Cartesian plane Center of a circle Center of a rotation Center of gravity Central angle of a circle Centroid Chord of a circle Circle Circle circumscribed about a triangle Circle inscribed in a triangle Circularity Circumcenter Circumference Clockwise Coincidental lines Collinear Compass Complementary angles Composite transformation Concave Concave polygon Concentric circles Concentric circles Concurrent lines Conditional Cone Congruence transformation Congruent Congruent circles Congruent figures Congruent triangles Conic section Conic solid Conjecture Consecutive angles Consecutive sides Consecutive vertices Consequent Constant of an equation Construction Contraction Contra positive Converse Converse theorem Convex polygon Convex quadrilateral Convex set Coordinate Coordinate geometry Coordinate plane Coordinates Coplanar Corollary to a theorem Corresponding angles Cosine of an angle Coterminal angles Counterclockwise Counterexample Cross section Cylinder Cylindrical solid Cylindrical surface Decagon Degree measure of an angle Diagonal Diameter Dilation Dimensions Direction Direction of a translation Discrete Line Distance Distance between 2 parallel lines Dodecagon Dot Drawing Duodecagon Edge Empty set Ends of a kite Enneagon Equal angles Equal triangles Equiangular Equidistant Equilateral Equilateral triangle Even node Exclusive or Existential statement Expansion Exterior angles Exterior of an angle Extremes Face Family tree Frieze pattern Fundamental region Geometric mean Given Glide reflection Goldback's Conjecture Grade Graph theory Great circle Grid Half-plane Harmonic mean Hemisphere Heptagon Hexagon Hidden lines Hierarchy Horizontal line Hypotenuse Icosahedron Identity reflection Identity transformation If-Then statement Image Improper subset Indenter Infinite Initial side Inscribed angle Instance of a sentence Intercept Interior angles Interior of a circle Interior of an angle Intersecting planes Intersection of two sets A and B Inverse Irrational number Irregular polygon Irregular region Isometry Isosceles trapezoid Isosceles triangle Kite Lattice points Leg of a right triangle Limit Line Line number Line of reflection Line perpendicular to a plane Line segment Line symmetry or reflection symmetry Linear equation Linear pair Linear term of an equation Lines of sight Location Locus Magnitude Magnitude of a rotation Magnitude of a translation Major arc Mapping Matrix Mean Meaning Means Measure Measure of an arc Median Median of a triangle Midline Midline theorem Midpoint Minor arc Net Network N-gon Node Nonagon Nonconsecutive angles Nonconsecutive sides Nonconsecutive vertices Nonconvex set Non-Euclidean geometry Non-included side Non-overlapping regions Nonperspective drawing Null set Number line Oblique line Oblique prism or cylinder Obtuse angle Obtuse triangle Octagon Odd node One-dimensional One-sided interior angles Opposite faces Opposite rays Opposite side Ordered pair Ordered triple Orientation Orthocenter Overlapping triangles Parallel lines Parallel planes Parallelepiped Parallelogram Pentadecagon Pentagon Perimeter of a polygon Perimeter of a triangle Perpendicular bisector Perpendicular lines Perpendicular planes Perspective Perspective drawing Pi Pixel Plane Plane figure Plane geometry Plane section Platonic solid Point Point of concurrency Point of intersection Point of tangency Polarity of a variable Polygon Polygonal region Polyhedron Postulate Prism Proof Proof by contradiction Proper subset Proportion Proportional Protractor Prove Pyramid Pythagorean theorem Pythagorean triple Q.E.D. Q.E.F. Quadrangle Quadratic equation Quadratic term of an equation Quadrilateral Radii Radius Radius of a circle Rate Ratio Ratio of similitude Ray Rectangle Rectangular solid Reference angle Refine Reflecting line Reflection Reflection image Reflection notation Reflection symmetry Reflex polygon Region Regular polygon Regular pyramid Resolution Rhombus Right angle Right cone Right cylinder Right prism Right triangle Rotation Rotation symmetry SAS Scale factor Scalene triangle Secant (line) Secant to a circle Sector Segment Semicircle Set Side of a polygon Side-angle-side (SAS) congruence Side-angle-side (SAS) similarity Side-side-side (SSS) congruence Side-side-side (SSS) similarity Similar Similar figures Similar triangles Similarity transformation Sine of an angle Size change Size change factor Size transformation Skew lines Slant height Slide Slope Small circle Solid Solid geometry Space Sphere Square     SSS Straight angle Subroutine Subset Sufficient condition Supplementary angles Surface Surface area Symmetry Symmetry line Tangent Tangent (line) Tangent of an angle Tangram Tessellate Tessellation Tetragon Theorem Three-dimensional Tilt Torus Transformation Transformation notation Translation Translation symmetry Transversal Trapezoid Triangle Triangle inequality Triangulate Tridecagon Trigon Two-dimensional Undecagon Union of two sets A and B Universe Van Hiele levels Vanishing line Vanishing point Vector Venn diagram Vertex Vertex angle Vertex of a conic solid Vertex of a polygon Vertex of an angle Vertical angles Vertical line View Volume Wedge Zero angle Zero-dimensional

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