Etnomathematics: A Flat-Build Application of a Quadrilateral in Masjid Agung Pondok Tinggi Kota Sungai Penuh

Mathematics and culture are interrelated to each other, which are found in everyday life. Various mathematical concepts can be explored and found in culture. Mathematical concepts can be seen in cultural products in the form of artifacts such as the Masjid Agung Pondok Tinggi. The Masjid Agung Pondok Tinggi can be a source of learning mathematics, because there are concrete mathematical concepts that are immediately seen by students. The purpose of this research is to explore what concepts exist in the building of Masjid Agung Pondok Tinggi which can be used as a source of learning mathematics and as an effort to develop Etnomathematics in mathematics learning. The Data is collected through exploration, observation, documentation, and literature studies. The results of the study found that in the construction of the Masjid Agung Pondok Tinggi had used mathematical concepts, even though the people in the past did not know how the concept of construction of buildings such as angles, symmetries, rectangles. Construction of the Masjid Agung Pondok Tinggi implements one of the mathematical sciences, namely geometry, one of the concept of a rectangle which includes a square, rectangle, and trapezium. Learning concrete ethnographic objects can facilitate students to understand abstract mathematics