Answer
Rectangular coordinates: $(4.21, 1.58)$
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Work Step by Step
In polar coordinates, the first number represents the value for $r$, and the second number represents the value for $\theta$.
$(-4.5, 3.5)$
Thus: $r = -4.5$ and $\theta = 3.5$
Knowing that $x = rcos(\theta)$ and $y = rsin(\theta):$
$x = rcos(\theta) = (-4.5)(cos(3.5)) \approx 4.21$
$y = rsin(\theta) = (-4.5)(sin(3.5)) \approx 1.58$