ClipArt ETC
Illustration used to prove that all right angles are equal.

Equal Right Angles

Illustration used to prove that all right angles are equal.

Illustration showing angles 1 and 2 are supplementary and angles ACD and DCB are supplementary. Also, Angles ACD and DCB are right angles.

Supplementary and Right Angles

Illustration showing angles 1 and 2 are supplementary and angles ACD and DCB are supplementary. Also,…

Illustration of a right circular cone resting on an element such that the vertex is on the bottom and a vertical and horizontal element meet at a right angle.

Right Circular Cone on Side

Illustration of a right circular cone resting on an element such that the vertex is on the bottom and…

This is an architectural tool, which facilitates the use of drawing straight lines and right angles, similar to modern T-squares.

Drafting Appliance

This is an architectural tool, which facilitates the use of drawing straight lines and right angles,…