Illustration of 2 similar right decagonal prisms. Both have regular decagons for bases and rectangular…

Illustration of 2 similar right heptagonal/septagonal prisms. Both have regular heptagons/septagons…

Illustration of 2 similar right hexagonal prisms. The height of the prism and length of the side of…

Illustration of 2 similar right hexagonal prisms. The height of the prism and length of the side of…

An geometric illustration of the algebraic product of (x+y)(x+y).

Illustration of a hollow right rectangular pyramid. The base is a rectangle and the faces are isosceles…

Illustration of a right rectangular pyramid with hidden edges shown. The base is a rectangle and the…

Illustration of a right rectangular pyramid with hidden edges shown. The base is a rectangle and the…

Illustration of a right rectangular pyramid with hidden edges shown. The base is a rectangle and the…

Illustration of a non-right, or skewed, rectangular pyramid with hidden edges shown. The base is a rectangle…

Illustration of 2 right rectangular pyramids with hidden edges shown. The rectangular bases are congruent,…

Illustrations to show quadrilaterals with lines joining the midpoints of the sides of any quadrilateral,…

Tangrams, invented by the Chinese, are used to develop geometric thinking and spatial sense. Seven figures…

Tangrams, invented by the Chinese, are used to develop geometric thinking and spatial sense. Seven figures…

Tangrams, invented by the Chinese, are used to develop geometric thinking and spatial sense. Seven figures…

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

Rectangle with dimensions labeled. Rectangle can be used to calculate area.

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

An illustration of a rectangle with lengths a and b and area ab.

An illustration of composite rectangle with lengths a, b, and c with area ac + bc. This illustration…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The lower…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The lower…

The illustration of a rectangular pyramid unfolded by creating edges equal length to the base and meeting…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right hollow rectangular pyramid that has been cut by a plane parallel to the base.…

Illustration of a right hollow rectangular pyramid that has been cut by a plane parallel to the base.…

Popcorn box that is in the shape of a frustum of a rectangular pyramid.

In military affairs, a narrow ditch or trench by which approach is made to a fortress or designed place…

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

A style of chair designed by Thomas Sheraton. This chair takes on a rectangular back.

Illustration of a square inscribed in a square. The interior square is rotated 45° in relation to…

Illustration of 12 congruent squares that have the same center. Each square has been rotated 7.5°…

Illustration of 16 congruent squares that have the same center. Each square has been rotated 5.625°…

Illustration of 2 concentric squares whose vertices are connected by line segments.

Illustration of 2 congruent squares that have the same center. One square has been rotated 45° in…

Illustration of 3 congruent squares that have the same center. Each square has been rotated 30°…

Illustration of 4 congruent squares that have the same center. Each square has been rotated 22.5°…