Geometry in Pictures Book 1 is the sixth book in the series, looking at angles, rotational & line symmetry and parallel lines. The sum of the angles in a triangle is shown with demonstrations and transformational reasoning and formally proved. The interior and exterior angles of polygons and the perimeters of polygons. Congruence and the properties of translations, rotations and reflections. Tessellations leading into area, and the area of the rectangle, parallelogram, triangle and trapezium. Proving and applying Pythagoras’ theorem, Pythagorean triples and the Set Square triangles. There are galleries to appreciate movement, and review questions at the end of sections.

The review questions require iOS 10 or higher.