An Elementary Geometry

A B C A B D ABCD adjacent adjacent angles altitude angle ABC apothem base and altitude centre chord circ circumference cone construct the triangle convex surface Corollary cylinder diagonals diameter distance divided dodecagon equal altitudes equally distant equilateral feet frustum given angle given circle given line given point given side half the arc hexagon homologous sides hypothenuse included angle infinite number inscribed internal angles intersection isosceles triangle Let ABCDEF line joining lines A B measured by half mutually equiangular number of sides opposite sides parallelogram parallelopiped perimeter perpendicular plane parallel quadrilateral radii radius ratio rectangle regular polygon respectively equal rhombus right angles right prism right pyramid right triangle Scholium secant segment similar triangles slant height sphere tangent THEOREM VII trapezoid triangle ABC triangles are equal vertex