A helpful scientific calculator that runs in your web browser window.
Holt Online Learning

The meaning of 'adjacent arcs' and how their arc lengths can be added.
Math Open Reference

Definition and properties of a sector  a pieshaped part of a circle..
Math Open Reference

Gives examples of problems with intercepted arc, central angle, and angles inside and outside the circle.
Online Math Learning

Finding the radius of an arc or segment given its height and width.
Math Open Reference

Peripheral angle: see 'inscribed angle'
Math Open Reference

Difference between major and minor arcs. How they can be ambiguous.
Math Open Reference

Definition of arc length and formula to calculate it from the radius and central angle of the arc.
Math Open Reference

Shows how a central angle can intercept or 'cut off' an arc
Math Open Reference

Definition and properties of an arc
Math Open Reference
