Riders in Geometry

ABCD allied angles alternate segment altitudes angle BAC angle of 30 angle-sum theorem angles equal AÔB base Calculate circle are equal circles intersect circles touching circumcircle common chord concyclic congruent constant length cyclic quadrilateral diameter Draw drawn parallel equal and parallel equal angles equal chords equal in area equidistant equilateral triangle Exercise exterior angle figure Find the locus fixed points given point Hence Ideas Illustrative Riders inscribed internal bisector intersecting circles isosceles triangle lines are drawn median meet the circumference meets BC opposite angles opposite sides parallel chords parallel straight lines parallel to BC parallelogram pentagon point in BC point of intersection produced meet Pythagoras quadrilateral ABCD radius rectangle properties rhombus right angles side BC square straight line joining suggests symmetry tangent terms of angles third side trapezium triangle ABC vertices