An Elementary Geometry: Plane, Solid and Spherical

A B C ABCD adjacent angles altitude angles are equal apothem bisecting the angles centre chord circumference construct the triangle convex surface Corollary diagonals diameter dicular diedral angles distance divided dodecagon draw edges equal angles equal bases equally distant equivalent face angles feet frustum given angle given line given point given side hence homologous lines hypothenuse intersection isosceles triangle line joining line parallel lines bisecting lines drawn locus middle points mutually equiangular number of sides opposite sides parallel planes parallelogram parallelopiped perimeter perpen perpendicular plane MN polar triangle polyedral angle polyedrons produced proposition pyramid quadrilateral radius ratio rectangle regular polygon respectively equal right angles right triangle Scholium segments similar sphere spherical angle spherical polygon spherical triangle square tangent tetraedron THEOREM triangle ABC triangle is equal triangular prism triedral vertex vertices