Khan Academy Inscribed Angles
Mathisfun Circle Theorems
Calculation #1
Calculations #2
Construction Ideas from mathisfun
Construction: Parallel Lines
Use the tools provided in the tool bar to draw one or more circles between the parallel lines, such that the parallel lines are tangent to the circles. Make your circles tangent to adjacent circles too!
Construction: Oblique Lines
Use the tools provided in the tool bar to draw a circle between the lines such that both lines are tangent to the circle.
Euclid’s Elements: How did Euclid say it?