Three squares and three shared vertices. Prove that the orange quadrilateral is in fact a parallelogram.
Categories
The orange belt
Month: June 2021
Categories
The cleaver
Four squares, a rectangle and a circle. What is the proportion brown : grey?
Categories
The green field
A square is divided in two quadrilaterals of given area. What fraction of the square’s perimeter is red?
Categories
The twin triangles
Two squares share a vertex. Prove that the red triangle is congruent to the blue one.
Categories
The partial eclipse
Two circles and a radius connecting their centres. What is the length of the parallel chord?
Categories
Ice cube
A rectangle and a square. What is the proportion purple : blue?
Categories
The hourglass
A rectangle with two crossing line segments. What’s the minimal shaded fraction?
Four quarter circles of radius 1, each containing a square. What is the blue area?
Categories
Below the tree line
A triangle is split in two. What is the area of the green quadrilateral in terms of lengths a and b?
Categories
Tympanum II
A regular pentagon with a diagonal. What is the top angle of the isosceles triangle?