Find the side of a square whose area is equal to the area of a rectangle with sides 0.5 and 2.

1) The area of the rectangle is:
Sп = a * b,
where Sп is the area of the rectangle, a is the length, b is the width.
Sп = 2 * 0.5 = 1 (conventional unit square).
2) The area of the square is:
Sk = t ^ 2, where
Sк – square area, t – square side.
Sк = Sп (by condition). Then
t ^ 2 = 1;
t = √1;
t = 1 (conventional unit).
Answer: t = 1 conventional unit.