Two squares of which three vertices form an isosceles triangle. What is the angle α?
Fair and square

Two squares of which three vertices form an isosceles triangle. What is the angle α?
A circle and a triangle with two sides tangent to the circle and a side connecting the tangency points. The line segment of the circle centre to the triangle apex is shown. Prove that α = β.
A square with its diagonal and a circle. If red is equal to blue, what’s the angle α?
Three squares and two line segments. What’s the angle α?
Two regular pentagons and two diagonals. What’s the angle α?
Two squares and two diagonals. Prove that the angles α and β are equal.
A semicircle with two inscribed circles tangent to an altitude. What’s the angle α?
Two tangent circles and two red tangent line segments. The three tangency points are shown. What is the angle β in terms of the angle α?
A quarter circle with two inscribed squares. What’s the angle α?
A square and an overlapping isosceles triangle. What is the angle α?