Why can’t a rectangle be a square?

Answered by Jeremy Urbaniak

A rectangle is a type of quadrilateral, which means it is a polygon with four sides. What distinguishes a rectangle from other quadrilaterals is that it has four right angles, or 90-degree angles. This property makes it a special type of shape with specific characteristics. However, not every rectangle can be considered a square.

The defining feature of a square is that it has four equal sides. In other words, all of its sides have the same length. This is not a requirement for a rectangle. While a rectangle can have two pairs of equal sides, the other two sides can have different lengths. This means that rectangles can have varying proportions, with one pair of sides being longer or shorter than the other pair.

To illustrate this, let’s consider some examples. Imagine a rectangle with two sides measuring 6 units and the other two sides measuring 4 units. This is a valid rectangle since it has four right angles, but it does not meet the criteria to be classified as a square because its sides are not all equal.

On the other hand, if we have a rectangle with all four sides measuring 5 units, then we have a square. In this case, the rectangle satisfies the condition of having four right angles, and its sides are also equal in length. Therefore, it can be classified as both a rectangle and a square.

It is important to note that we cannot assume all rectangles are squares or vice versa. While every square is indeed a rectangle, not every rectangle can be considered a square. The distinction lies in the requirement for equal side lengths in a square, which is not necessary for a rectangle.

In real-life situations, this difference between rectangles and squares can be observed easily. Consider a computer screen or a piece of paper. These objects are often rectangular in shape but not necessarily squares. The screen or paper can have different proportions, with one pair of sides longer or shorter than the other. This variation in proportions allows for different uses and applications.

A rectangle cannot be considered a square because a square has the additional requirement of having four equal sides. While all squares are rectangles, not all rectangles are squares. The distinction is based on the equality of side lengths, with rectangles allowing for varying proportions while squares have equal sides.