Example 5
A square is a quadrilateral with two pairs of parallel opposite sides, consecutive sides that are perpendicular, and all sides congruent, meaning they have the same length.
Quadrilateral ABCD has vertices A (–1, 2), B (1, 5), C (4, 3), and D (2, 0).
Determine if this quadrilateral is a square.
Note: Drag the blue points to try different figures.