Khan Academy
Khan Academy: Area of Inscribed Equilateral Triangle
A worked example of finding the area of an equilateral triangle inscribed within a circle who's area is known. This video uses Heron's formula and some trigonometry.
Khan Academy
Khan Academy: Geometric Constructions: Circle Inscribed Square
Sal constructs a square that is inscribed inside a given circle using compass and straightedge.
Khan Academy
Khan Academy: Geometric Constructions: Circle Inscribed Regular Hexagon
Sal constructs a regular hexagon that is inscribed inside a given circle using compass and straightedge.
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Khan Academy: Geometric Constructions: Triangle Inscribing Circle
Sal constructs a circle that inscribes a given triangle using compass and straightedge.
Khan Academy
Khan Academy: Geometric Constructions: Triangle Circumscribing Circle
Sal constructs a circle that circumscribes a given triangle using compass and straightedge.
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Khan Academy: Inscribed Shapes: Angle Subtended by Diameter
One method using an inscribed angle intercepting a diameter of a circle.
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Khan Academy: Proof: Right Triangles Inscribed in Circles
Proof showing that a triangle inscribed in a circle having a diameter as one side is a right triangle.
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Khan Academy: Inscribed Quadrilaterals Proof
Sal uses the inscribed angle theorem and some algebra to prove that opposite angles of an inscribed quadrilateral are supplementary.
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Khan Academy: Proof: Perpendicular Radius Bisects Chord
Simple proof using RSH postulate to show that a radius perpendicular to a chord bisects it
Khan Academy
Khan Academy: Inscribed Shapes: Find Diameter
Find the diameter of a circle using an inscribed right triangle.
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Khan Academy: Solving Inscribed Quadrilaterals
Example showing supplementary opposite angles in inscribed quadrilateral.
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Khan Academy: Geometric Constructions: Circle Inscribed Equilateral Triangle
Sal constructs an equilateral triangle that is inscribed inside a given circle using compass and straightedge.
Khan Academy
Khan Academy: Proof: Radius Is Perpendicular to a Chord It Bisects
Sal proves that if a radius in a circle is drawn so it bisects a chord, then the radius is also perpendicular to that chord. The proof uses SSS congruence.