How do you convert the polar coordinate ( 11.3991 , -0.5856 )into cartesian coordinates?

$x = 9.49979$ and $y = - 6.30028$

Explanation:

From the given data $r = 11.3991$ and $\theta = - 0.5856$radian

$x = r \cos \theta$
$x = 11.3991 \cdot \cos \left(- 0.5856\right)$ make sure your calculator is set to angle in radian mode

$x = 9.49979$

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also
$y = r \cdot \sin \theta$
$y = 11.3991 \cdot \sin \left(- 0.5856\right)$ make sure your calculator is set to angle in radian mode
$y = - 6.30028$

God bless....I hope the explanation is useful..