Geometry
GradesGrade 3GeometryClassifying Quadrilaterals

Classifying Quadrilaterals

🔷 Geometry
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Classifying Quadrilaterals

All four-sided shapes are quadrilaterals — but they come in many flavors!

A QUADRILATERAL is any closed flat shape with exactly 4 sides and 4 angles. Squares, rectangles, rhombuses, trapezoids, and parallelograms are all quadrilaterals — but they each have special features that set them apart.

Key quadrilaterals and their attributes:

1SQUARE — 4 equal sides, 4 right angles (90°)
2RECTANGLE — opposite sides equal and parallel, 4 right angles
3RHOMBUS — 4 equal sides, opposite sides parallel, angles may not be 90°
4PARALLELOGRAM — 2 pairs of parallel sides, opposite sides equal
5TRAPEZOID — exactly 1 pair of parallel sides
6GENERAL QUADRILATERAL — 4 sides, no special parallel sides

Has 4 right angles

SquareRectangle

Has 4 equal sides

SquareRhombus

Has 1 pair of parallel sides

Trapezoid

A square is the most special — it has BOTH 4 equal sides AND 4 right angles!

🔍Is every square a rectangle?
A rectangle needs: opposite sides equal, 4 right angles.
A square has: ALL sides equal, 4 right angles.

Yes! Every square fits the definition of a rectangle.
But NOT every rectangle is a square (only when all sides are equal).
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Attributes are features we can observe: number of sides, angle sizes, which sides are equal, which sides are parallel.

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Remember This!

A right angle looks like the corner of a piece of paper. Mark right angles with a small square symbol (⊾) in the corner when drawing quadrilaterals.

✏️ Try It!

Which quadrilateral has exactly 4 equal sides but does NOT necessarily have right angles?

Take Quiz 📝 — 25 Questions