Grade 4 · Maths · Lessons
Sorting by the sides
▭rectangle🔺triangle◇rhombus⏢trapezoid
Sort by the sides.The big ideaParallel sides never meet. Perpendicular sides meet at a right angle.
How it works
Parallel sides never meet. Perpendicular sides meet at a right angle.
Sort shapes by parallel sides and right angles.
A rectangle has two pairs of parallel sides and four right angles.
Example 1: A rhombus
- A rhombus has 4 equal sides and slanted corners.
- Check its corners: none are square.
- It has no right angle.
Example 2: A triangle
- A triangle has 3 sides.
- No two sides stay the same distance apart.
- It has no pairs of parallel sides.
Example 3: A turned rectangle
- A rectangle is turned on its side.
- Turning doesn't change it.
- It still has two pairs of parallel sides.
Words to know
- parallel
- Lines that never meet.
- right angle
- A square corner, 90 degrees.
Watch out
- Turning a shape doesn't change its sides.
- A square is a rectangle.
- A rhombus isn't a square unless it has right angles.
Try it
- How many pairs of parallel sides does a triangle have?
- Does a rectangle have right angles?
- Does a rhombus always have a right angle?
- How many pairs of parallel sides does a trapezoid have?
Answers: 1. none · 2. yes, four · 3. no · 4. 1
For grown-upsCut shapes from paper and sort them by parallel sides and right angles.