# Curve

Wikipedia open wikipedia design.A **curve** is a line that turns or bends. A curved line is never straight, and a curved surface is a surface that is never flat. Some curves can be drawn on paper, but some curves, like a helix, can only be seen in 3-D. A circle is a curve that can be described with the formula *x*^{2} + *y*^{2} = *r*^{2}. *x* and *y* are used as in a Cartesian coordinate system, and *r* is the radius of the circle (distance from the center to the outside). Many other curves can also be described with a formula like that.

## Related pages[change | change source]

Wikimedia Commons has media related to .Curves |

This page is based on a Wikipedia article written by contributors (read/edit).

Text is available under the CC BY-SA 4.0 license; additional terms may apply.

Images, videos and audio are available under their respective licenses.