Fold Perpendicular: Fold the circle again, aligning the edge of the circle with the diameter line you just created. Make sure ...

When calculating angles using a circle theorem, always state which theorem applies. It may not be possible to calculate the missing angle immediately. It may be necessary to calculate another angle ...

Circle theorems are properties that are true for all circles, regardless of their size. There are six theorems to learn and recognise. Questions can have a combination of theorems. It is important to ...