Control the angle at the centre.[br][br]Notice how the red, green, blue line segments get bigger/smaller.[br][br]At what angle does the green line segment become longer than the red line segment?[br][br]At what angle does the blue line segment become longer than the red line segment?[br][br]Given that the angle permitted ranges from zero to 90°, whats the shortest/longest green line segment?[br][br]What's the shortest/longest red line segment?[br][br]What's the shortest/longest blue line segment?[br][br]How many right angled triangles are in the diagram?[br][br]What does Pythagoras' say about those right angled triangle(s)?