The Essentials of Geometry (plane)

ABCD acute adjacent altitude angles are equal arc BC base bisector bisects called centre chord circle circumference circumscribed coincide common construct describe diagonals diameter divided Draw line drawn equal equally distant equilateral equivalent EXERCISES exterior angle extremities fall figure Find follows Geometry given Given line given point greater Hence hexagon hypotenuse included inscribed intersect isosceles triangle length less line joining manner mean measured meeting middle point one-half opposite sides parallel parallelogram passes perimeter perpendicular plane polygon PROBLEM produced Proof Prop proportional Prove quadrilateral radii radius ratio rectangle regular inscribed Required respectively right angles right triangle segment side BC similar square straight line surface tangent THEOREM third transversal trapezoid triangle ABC unit values vertex vertices