- Matt JamesSlopes of parallel linesSlopes of Perpendicular LinesPoints of ConcurrencyStation 2 - Orthocenter ActivityCircumcenter ActivityLengths of parts of medians using the centroidExterior Angle InequalityAngle from Side and Side from Angle InequalitiesTriangle Side InequalityTriangle Proportionality TheoremProportional segments of parallel linesProportional segments by the angle bisector of trianglePythagorean Theorem ProofPythagorean Theorem Proof 2Classifying Triangles from the Pythagorean TheoremAltitude Forms Similar Triangles AnimationRight Triangle Altitude RatiosSolving Right Triangles QuizInterior Angles of PolygonsTranslationCoordinate Notation Translation QuizRotation of points in a triangle quizDouble Reflection Over Parallel LinesDouble Reflection Over Intersecting LinesCongruent chords in a circleFinding the diameter of a broken dinner platemeasure of inscribed angles = 1/2 the intercepted arcDemonstration of the Inscribed AngleArc with Tangent Measures - QuizAngle Measures from Intersection inside circleFinding Measures of Tangent/Secant Arcsintersection of secants, chords, and tangents of a circleLength of Chords, Secant Segments, and Tangent Segmentsformula for Area and Perimeter of CircleFinding the Area of a regular polygonRotating Pyramid