A regular hexagon, a circle through its red centre and two line segments. What’s blue : orange?
An equilateral triangle inside a rectangle. What is red : yellow : blue?
Two similar triangles ABC and EBD. Two line segments meet at point F. Prove that ABFC and EBDF are cyclic quadrilaterals.
Two squares sharing a vertex. Two vertices are connected by a line segment. What is yellow : green?
A quadrilateral and a triangle. What’s the angle α?
A regular pentagon and a circular arc through its red centre. What’s the proportion α : β?
A regular nonagon and four equilateral triangles. The purple and yellow triangles share a vertex. Prove that the yellow triangles also share a vertex.
An equilateral triangle with a circular arc through its red centre and two vertices. If the yellow area equals the green one, what’s the angle α?
A parallelogram and four equilateral triangles. What is yellow : green?
A square with two right angles. What fraction is yellow?