## Elementary Synthetic Geometry of the Point, Line and Circle in the Plane |

### Other editions - View all

### Common terms and phrases

ABCD Algebra altitude becomes bisects c.p.-circles centre of similitude centre-line chord of contact circles touch circumcircle co-axal coincide collinear concurrent concurrent lines concyclic congruent corresponding cut the circle denote diagonals diameter divided double points end-points equal angles equianharmonic equilateral triangle excircle external bisector fixed point given circles given line given point harmonic range Hence hexagram homographic homologous hypothenuse incircle internal angles inverse points isosceles joins LAOB line-segment locus median middle point nine-points circle opposite sides orthogonally pair parallel parallelogram passes pencil perpendicular perspective plane point of contact point of intersection polar reciprocal Proof quadrangle radical axis radical centre radii radius rectangle regular polygon rhombus right angle right bisector rotation secant similar Similarly square straight angle symbol SYNTHETIC GEOMETRY tangent tensor theorem Theorem.-The three circles transversal vertex vertices