Elements of Geometry

A B C D AABC AACB ABCD adjacent angles apothem arc A B base and altitude centre centre of symmetry chord circumscribed coincide construct a square COROLLARY decagon describe an arc diagonals diameter divided Draw equal arcs equal distances equal respectively equiangular equiangular polygon equilateral equilateral polygon exterior angles figure given circle given line given polygon given square hexagon homologous sides hypotenuse isosceles Let A B Let ABC line A B measured by arc middle point number of sides parallelogram perpendicular plane polygon ABC polygon similar PROBLEM prove Q. E. D. PROPOSITION quadrilateral radii radius equal ratio rect rectangles regular inscribed regular polygon required to construct right angles right triangle SCHOLIUM segment semicircle similar polygons square equivalent subtend symmetrical with respect tangent THEOREM triangle ABC vertex vertices