Chapter 7, Problem 61P

How much work is done by a force $\stackrel{\to }{F}$= (2x N) $\hat{i}$ + (3 N) $\hat{j}$, with x in meters, that moves a particle from a position ${\stackrel{\to }{r}}_i$=(2 m) $\hat{i}$ + (3 m) $\hat{j}$ to a position ${\stackrel{\to }{r}}_f$= -(4 m) $\hat{i}$− (3 m) $\hat{j}$?