Precalculus (10th Edition)

$(3.79,-7.16)$
By definition, we know that $x=r\cdot \cos(\theta)$, $y=r\cdot \sin(\theta)$. Here, we were given $r=8.1 \text{ and } \theta=5.2$. Hence, after plugging these in: $x=8.1\cdot \cos(5.2)\approx3.79$ $y=8.1\cdot \sin(5.2)\approx-7.16$ The point has coordinates $(3.79,-7.16)$ in the rectangular coordinate system.