A trapezium containing three right angles is split in two. What is the proportion of the areas yellow : blue?
Month: April 2021
The fallen pine
Two congruent isosceles triangles and three lines. Prove triangle AEF is also isosceles.
The color fan
Two congruent rectangles share a vertex. Given that the three coloured areas are equal, what is the width x?
The right angle
Two triangles inside a quarter circle. What is their area proportion?
The triangle quartet
A square is divided into four triangles. The red area equals the blue area. What is the angle α?
The corner stone
Four squares inside another square. What fraction is yellow?
The bigger picture
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.
La Flèche Wallonne
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?
The navel orange
Two quarter circles and a semicircle inside a circle. What fraction of the circle is shaded by the semicircle?