Angles at the Circle
This app is about angles at the circle. The following terms and their properties are illustrated:
- Central angle (angle at the center)
- Inscribed angle (angle at the circumference)
- Angle between chord and tangent
The central angle (blue) can be increased or decreased by using the slider. By dragging with pressed mouse button
you can vary the vertex of the inscribed angle (red).
- Inscribed angles intercepting the same arc have the same measure.
- The measure of any inscribed angle is half the measure of the corresponding central angle.
- The angles between a chord and a tangent have the same meausure as an inscribed angle
and half the measure of the central angle.