Illustration to show that if an angle is bisected, and if a line drawn through the vertex perpendicular…

Illustration to show that the bisectors of two supplementary adjacent angles are perpendicular to each…

Illustration to show that the bisector of one of two vertical angles bisects the other.

Illustration to show that the bisector of two pairs of vertical angles formed by two intersecting lines…

Illustration of a dihedral angle bisected by a plane. "Every point in a plane which bisects a dihedral…

Illustration to show that the bisector of the vertical angle of an isosceles triangle bisects the base,…

Illustration to show that if through any point in the bisector of an angle a line is drawn parallel…

Illustration used to show "The two perpendiculars to the sides of an angle from any point in its bisector…

Illustration used to show "The two perpendiculars to the sides of an angle from any point not in its…

Illustration showing that the bisector of a given angle is the locus of points equidistant from the…

Illustration of the construction used to bisect a given line.

Illustration showing that if two angles of a triangle are equal, the bisectors of these angles are equal.

Illustration used to prove "The line joining the mid-points of two sides of a triangle is parallel to…

Illustration to show that if the diagonals of a quadrilateral bisect each other, the figure is a parallelogram.

Illustration to show that if the diagonals of a parallelogram are equal, the figure is a rectangle.

Illustrations to show that if two parallel lines are cut by a transversal, the bisectors of the interior…

Illustration used to prove "The line bisecting one side of a triangle and parallel to another side bisects…

Illustration used to prove "The bisectors of the angles of a triangle are concurrent in a point which…

Illustration to show that the bisector of an exterior angle of an isosceles triangle, formed by producing…

Illustration of a triangle showing that when a line parallel to the base of a triangle bisects one side,…

Illustration to show perpendicular bisectors in a triangle. It is known as the circumcenter.

Illustration to show angle bisectors in a triangle. It is known as the incenter.

Illustration to show that if one of the legs of an isosceles triangle is produced through the vertex…

Illustration to show that if the lines joining the middle points of the sides of a triangle divide the…

Illustration used to show the various parts of a triangle: sides, angles, medians, altitudes, bisectors,…

Illustration to show that the perpendicular bisector of the base of an isosceles triangle passes through…

Illustration used to prove "The perpendicular bisectors of the sides of a triangle are concurrent in…