Answer
$(9.30, 0.47)$
Work Step by Step
Solve for $r$ using the formula $r=\sqrt {x^{2}+y^{2}}$ to obtain:
$$r=\sqrt {(8.3)^{2}+(4.2)^{2}}=9.30$$
Since $(8.3, 4.2)$ is in the first quadrant, then
$$\theta=\tan^{-1}\left(\frac{y}{x}\right)=\tan^{-1}\left(\frac{4.2}{8.3}\right)\approx0.47$$
Thus, the polar coordinates for the point $(8.3, 4.2)$ is $(9.30, 0.47)$..
