In the given figure (a square),identify the following vectors:
Equal vectors.

(N/A) Two vectors are said to be equal if they have the same magnitude and the same direction.
In the given square,vectors $\overrightarrow{a}$ and $\overrightarrow{c}$ have the same magnitude (side length of the square) but opposite directions.
Vectors $\overrightarrow{d}$ and $\overrightarrow{b}$ have the same magnitude (side length of the square) but opposite directions.
Looking at the directions of the vectors:
- $\overrightarrow{a}$ points to the right.
- $\overrightarrow{c}$ points to the left.
- $\overrightarrow{d}$ points downwards.
- $\overrightarrow{b}$ points downwards.
Therefore,vectors $\overrightarrow{d}$ and $\overrightarrow{b}$ are equal because they have the same magnitude and the same direction.