Can you prove that triangles are right-angled when $a^2+b^2=c^2$?
Can you prove the angle properties described by some of the circle theorems?
Can you make sense of these three proofs of Pythagoras' Theorem?
Can you prove that the opposite angles of cyclic quadrilaterals add to $180^\circ$?
Do you agree with Badger's statements? Is Badger's reasoning 'watertight'? Why or why not?
Can you use Proof by Induction to establish what will happen when you add more and more odd numbers?
$40$ can be written as $7^2 - 3^2.$ Which other numbers can be written as the difference of squares of odd numbers?
