2.3 Exercise 14

Given the displacement vector $\overset{\rightarrow}{D} = \left(3 \hat{i} - 4 \hat{j}\right) \text{m},$ find the displacement vector $\overset{\rightarrow}{R}$ so that $\overset{\rightarrow}{D} + \overset{\rightarrow}{R} = −4 D \hat{j}$.