# What is -pi in degrees?

##### 1 Answer
May 16, 2015

$- \pi$ radians $= - {180}^{o}$

A radian is the angle subtended by an arc of a circle of length equal to the radius. If a circle has radius 1, then an angle of 1 radian defines an arc whose curved length is 1. $2 \pi$ radians will take you once round the circle.

Degrees divide the angle of a complete circle into 360 divisions. ${360}^{o}$ takes you once round the circle.

So $2 \pi$ radians is the same as ${360}^{o}$ and $\pi$ radians is ${180}^{o}$.