The Elements of Geometry

ABCD adjacent angles alternate angles angles are equal angles equal angles opposite base bisect called chord circumcenter coincide common commutative law CONCLUSION construction CONTRANOMINAL COROLLARY cross-ratio describe diagonals diameter divided draw end point equal are congruent equal sects equivalent exterior angle figure frustum geometry given line given point given sect greater hypothenuse HYPOTHESIS included angle inscribed inscribed angle intercepted interior isosceles triangle less magnitudes meet mid-point multiples number of sides pair parallel parallelogram pass perigon perimeter perpendicular bisector prism prismatoid PROOF quadrant quadrilateral radii radius ratio rectangle rectangle contained Reflex Angle regular polygon right angle Rule of Inversion sect joining segment sphere spherical polygon spherical triangle square straight angle subtended supplemental surface symmetrical tangent tetrahedron THEOREM three sides transversal triangles are congruent vertex