Composition of the second volume of mathematical puzzles in the first grade of primary school;
Five isosceles right triangles (two small triangles, one middle triangle and two large triangles), one square and one parallelogram.
Tangram is an ancient traditional intellectual toy in China. As the name implies, it consists of seven boards.
Triangles, parallelograms, irregular polygons, players can also spell them into various graphics, images, animals, bridges, houses, towers and so on. Or some Chinese and English letters.