I have very fond memories of high school geometry. Memorizing theorems wasn't too hard, and solving proofs was like solving the logic puzzles that I did for fun anyway. But the theorems were scattered ...

Learn how to solve for an unknown variable using parallel lines and a transversal theorems. Two lines are said to be parallel ...

Circles have different angle properties, described by a number of theorems. This is one of two guides on circle theorems, with this guide covering the following: the angle subtended by an arc at the ...

It is important to remember other angles rules, such as angles on a straight line add up to 180°, and to recognise angles in parallel lines. Make sure you are confident in applying Pythagoras’ theorem ...