The formula for the area of a square is:

A = s^2

where A represents the area and s represents the length of a side.

You are given that the side is 5 units long.  Therefore s = 5.  Substitute 5 in for s in the formula and solve.

A = 5^2

A = 25

Answer:  25 square units 

The area of a rectangle, which is a quadrilateral with 4 sides, the opposite sides being parallel and the adjacent sides being perpendicular is given by the product of the length and the width. A square is a special type of rectangle with the length equal to the width.

The area of a square is therefore s*s, where s is the length of the side. Here the length of the side of the square is 5 units. The area of the square is 5*5 = 25 square units.

The required area of the square is 25 square units.

In determining the area of a square, one need only figure out the length of one side to fulfill the conditions of the formula, which is width times height.

By definition, a square consists of four equal sides.  This would mean that the formula for the area of a square consists of "squaring" the sides. If one side is five, then the other side, by definition, also has to be five.

In this light, take the 5 units and then "square" it, meaning to raise it to the second power.  This results in 5 ^2.  This equals 25.

Therefore, the area of this square would be 25 total units.