Skip to content
Exit presentation

Quadrilaterals

One shape, several names

A square sits in one box on the chart below. Rectangle fits. So does rhombus. So does parallelogram. Which is it?

Trapezium: at least one pair of sides parallel.
Step 1 of 5
  1. Trapezium: at least one pair of sides parallel.
  2. Parallelogram: both pairs of sides parallel.
  3. Rectangles: also all four corners 90°.
  4. Rhombuses: also all four sides equal.
  5. Squares: where both extras happen at once.

A square is all of them. It has all five names.

Rule: A square meets every list. So it has all five names. Every rectangle and every rhombus meets the parallelogram list too. Every parallelogram meets the trapezium list. Trapezium is the widest name. Square is the narrowest.

A rectangle 8 by 6 has two side lengths. So it misses the rhombus list. Rectangles and rhombuses overlap only in squares.

Use the best name, the one with the longest list. It tells you every fact on that name's list. A looser name tells you fewer.

Look at the shape. Tap how many of the five names it earns.

Loading lab…

Jump to lesson

This track

  1. 0 Start here
  2. 1 Four straight sides, joined up
  3. 2 The four angles come to 360°
  4. 3 A line to the corner across
  5. 4 Five names and what each one demands
  6. 5 What a parallelogram gives you
  7. 6 Checkpoint: sides, angles and the family
  8. 7 Diagonals that cut each other in half
  9. 8 A rectangle also has matching diagonals
  10. 9 A rhombus crosses at a right angle
  11. 10 One shape, several names
  12. 11 Building one from measurements
  13. 12 Checkpoint: diagonals, names and building
  14. 13 The big picture
  15. 14 Track quiz

Other tracks