Illustration used to prove that triangle EFD is equilateral given that triangle ABC is equilateral and…

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

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…

An illustration showing that the area of a regular polygon is equal to the area of a triangle whose…

Illustration used to show that two triangles are equal if the three sides of one are equal respectively…