A trapezium containing three right angles is split in two. What is the proportion of the areas yellow : blue?
Two congruent isosceles triangles and three lines. Prove triangle AEF is also isosceles.
Two congruent rectangles share a vertex. Given that the three coloured areas are equal, what is the width x?
Two triangles inside a quarter circle. What is their area proportion?
A square is divided into four triangles. The red area equals the blue area. What is the angle α?
Four squares inside another square. What fraction is yellow?
In a small square two perpendicular lines are drawn. A larger parallel square is constructed as shown. Prove it is a scaled copy of the smaller square but rotated 90° anticlockwise.
A triangle is divided in four. What is the black area?
A rectangle of height 2 is crossed by two line segments at right angles. What is its width?
Two quarter circles and a semicircle inside a circle. What fraction of the circle is shaded by the semicircle?