Answer
$$4.4996 - 5.3620i$$
Work Step by Step
$$\eqalign{
& 7\operatorname{cis} 310^\circ \cr
& {\text{Write in trigonometric form}} \cr
& = 7\left( {\cos 310^\circ + i\sin 310^\circ } \right) \cr
& {\text{Calculate }}\cos 310^\circ {\text{ and }}\sin 310^\circ \cr
& \cos 310^\circ \approx 0.6428 \cr
& \sin 310^\circ \approx - 0.7660 \cr
& {\text{,then}} \cr
& 7\left( {\cos 310^\circ + i\sin 310^\circ } \right) \approx 7\left( {0.6428 - 0.7660i} \right) \cr
& \approx 4.4996 - 5.3620i \cr} $$
