Elements of Plane Geometry

ABC and DEF ABCD altitudes angle formed Apply base bisector bisects called chord circle circum circumference circumscribed common consequent Construct contains CONVERSELY COROLLARY DEFINITION diagonals diameter difference divided Draw drawn EFGH equally distant equiangular equilateral triangle equivalent EXERCISE exterior angles externally extremities figure Find four given circle given line given point greater half homologous hypotenuse included intercepted interior isosceles triangle length less Let ABC limit line joining mean medians meet middle points opposite sides parallel parallelogram passes perimeter perpendicular point of intersection polygon prolonged Proof proportion PROPOSITION Prove quadrilateral radii radius ratio rectangle Required respectively right angles right-angled triangle secants segments Show sides similar square straight line Suggestion tangent THEOREM third trapezoid triangle ABC unequal vertex Whence