# What is the Cartesian form of ( -3, (-19pi)/8 ) ?

May 28, 2017

$\left(- 3 \cos \left(\frac{- 19 \pi}{8}\right) , - 3 \sin \left(\frac{- 19 \pi}{8}\right)\right)$
or
$\approx \left(- 1.15 , 2.77\right)$

#### Explanation:

Polar coordinates take the form $\left(r , \theta\right)$

Conversion of polar coordinates to rectangular as follows:
$x = r \cos \theta$
$y = r \sin \theta$

Therefore, $x = - 3 \cos \left(\frac{- 19 \pi}{8}\right) , y = - 3 \sin \left(\frac{- 19 \pi}{8}\right)$