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…

Isosceles Triangle with a dotted vertical line that is a line of symmetry.

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

Illustration showing that can be used to prove that the base angles of an isosceles triangle are equal.

Illustration of the construction used to create an isosceles triangle, given the bases and the sum of…

Illustration showing that if equal segments measured from the vertex are laid off on the arms of an…

Illustration showing that if equal segments prolonged through the vertex are laid off on the arms of…

Illustration showing that if equal segments measured from the end of the base are laid off on the base…

Illustration showing that if equal segments measured from the end of the base prolonged are laid off…

Illustration of 2 similar right pentagonal pyramids with hidden edges shown. The height of the pyramid…

Four different types of forms or shapes: right triangle, isosceles triangle, rectangle, and circle.

Illustration of a stepladder that is opened to form an isosceles triangle with the ground.

Illustration of a stepladder that is opened to form an isosceles triangle with the ground.

Illustration of a giant stepladder, sometimes called a skyscraper stepladder, that is opened next to…

Outlines of shapes (rectangle, parallelogram, isosceles triangle, double arrow, rhombus, hexagon) made…

Solutions for outlines of shapes (rectangle, parallelogram, isosceles triangle, double arrow, rhombus,…

Silhouette outlines of shapes (rectangle, parallelogram, isosceles triangle, double arrow, rhombus,…

Solutions for silhouette outlines of shapes (rectangle, parallelogram, isosceles triangle, double arrow,…

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