Or search by topic
Try a few examples with numbers to convince yourself this works.
You are told that the answer will always be a perfect square - so the factorisation should be easier than you might first think.
A 1 metre cube has one face on the ground and one face against a wall. A 4 metre ladder leans against the wall and just touches the cube. How high is the top of the ladder above the ground?
Four rods are hinged at their ends to form a convex quadrilateral. Investigate the different shapes that the quadrilateral can take. Be patient this problem may be slow to load.