Search Results for “Circle”
Cyclic Quadrilateral Theorem
The Cyclic Quadrilateral Theorem states that for a quadrilateral inscribed in a circle, the measures of opposite angles must add to 180 degrees. Drag the points and observe the angle measures to see how this theorem holds true.
Chord Angle Theorem
The chord angle theorem states that in an inscribed triangle (ABC) where A is the center of the circle and BC is a chord, and BDC is an inscribed triangle on the same chord, angle BDC must equal one half of angle BAC. Try changing the angle and moving point D and observe the theorem’s truth. Note: the measure of angle BDC is being constantly recalculated as point D is dragged, but it doesn't change because of this theorem.
N-Gon Approximating a Circle
This n-gon (regular polygon of n sides) has a variable number of sides. Changing the value for n demonstrates very visually how regular polygons of increasing numbers of sides, with the same radius, have a shape that increasingly approaches that of a circle.
Two Circle Trace
This trace follows the position of one circle as it moves along the path of the edge of another.
