Two squares share a vertex. Two other vertices are 4 units apart. A third green square has the centres as opposite vertices. What is its area?
The common ground

Two squares share a vertex. Two other vertices are 4 units apart. A third green square has the centres as opposite vertices. What is its area?
A regular hexagon and a square share a vertex. What is the area proportion square : hexagon?
A square contains a yellow right triangle with an area of 11. What is the square’s area?
A square, a semicircle and six line segments. What’s the angle α?
A square with several line segments. Prove that the blue ones are parallel.
A square with an extended side inside another square. What fraction of the latter is blue?
A square contains a right triangle. What fraction is red?
A triangle containing two congruent squares. Each square has 1/3 the perimeter and 1/6 the area of the triangle. What’s the triangle side length proportion a : b : c?
A circle containing an equilateral triangle and three squares. What fraction is purple?
Four squares and a rectangle. What’s the angle α?