POL019 · Quadrilaterals & polygons · Classes 7–9
Quadrilateral properties
Special quadrilaterals are defined by their sides, angles and diagonals. A square is a rectangle and a rhombus at the same time.
◇ ▭ ▱Quadrilateral properties
📐 Formula
square ⊂ rectangle ⊂ parallelogram; square ⊂ rhombus ⊂ parallelogram
✏️ Worked example
Rhombus: all four sides equal, and its diagonals bisect each other at right angles (red lines).
🌍 Where it is used
Identifying shapes in design, tiling and engineering.
❓ Quick check
Which always has diagonals of equal length?
🏋️ Practice
EasyIs every square a rhombus?
Answer: Yes
MediumIs every rhombus a square?
Answer: No
ChallengeWhich quadrilateral has exactly one pair of parallel sides?
Answer: Trapezium