Find the number of triangle in this figure? |
20 21 23 27 |
27 |
Naming the edges of the figure: We manually count the triangles as (GLK, DLJ, DJM, HMN, QRE, IRA, IPA, FPO) (BDO,CDQ, DLM, PRA, KFI, NEI, HJI, GJI,DKI, DNI) (DIE, DFI, DOA, DQA, GHI) (DCA, DBA) (DEF) (ABC) 8 + 10 + 5 + 2 + 1 + 1 = 27 |