[Free Registration/Login may be required to access all resource tools.] This study guide reviews the terminology for circles (tangent, arcs, central angles) and the equation for a circle.

The interactive tutorial examines the properties of central and inscribed angles intercepting a common arc in a circle. Learners use the applet to find central and inscribed angles.

Proving that an inscribed angle is half of a central angle that subtends the same arc.