Drag to explore

Make the inscribed angle exactly by changing the central angle.

Central Angle

Match the angles

Drag the correct measurements to the inscribed angles that subtend the blue arc.

Drop

Tap 90° angles

Tap the circles where the inscribed triangle creates a right () angle. Hint: Look at the center!

Balance to 180°

In a cyclic quadrilateral, opposite angles add up to . Find .

A B C D
+ =

Master of Circles!

You've mastered inscribed angles, cyclic quadrilaterals, and arcs.