Lesson · Grade 5 · Mathematics
Sorting Quadrilaterals by Sides and Angles
- Grade 5
- Mathematics
- 1 min 34 s
- British Columbia
- BC5-MA-31
A square, a rectangle, a rhombus, a parallelogram and a trapezoid are measured one at a time, with every side length and angle shown, and dropped into a sorting grid that asks two questions: are all four angles 90°, and are all four sides equal? The parallelogram and the trapezoid land in the same box, so parallel sides tell them apart: the parallelogram has two pairs, while this trapezoid has only one because its slanted sides would meet if they were made longer.
Anyone can watch two lessons on the website without an account. Signing in is free, no payment and no card, and opens three a day; Plus has no limit.
Loading
In one sentence
The question this lesson answers
How can we sort these five shapes?
Each one has four straight sides, so they are all quadrilaterals.
Transcript
What the lesson says
How can we sort these five shapes?
Each one has four straight sides, so they are all quadrilaterals.
They are a square, a rectangle, a rhombus, a parallelogram and a trapezoid.
First, are all four angles right angles, 90 degrees each?
Next, are all four sides the same length?
The square has four 90 degree angles and four 3 centimetre sides.
The rectangle has four 90 degree angles, but its sides are 4 and 3 centimetres.
The rhombus has 60 and 120 degree angles, but all four sides are 3 centimetres.
The parallelogram has 60 and 120 degree angles, and sides of 4 and 3 centimetres.
The trapezoid also has 60 and 120 degree angles, and sides of 6, 3, 3 and 3 centimetres.
The parallelogram and the trapezoid share a box, so how are they different?
Parallel sides never meet, even if we make them longer.
The parallelogram has two pairs of parallel sides.
This trapezoid has only one pair, because its slanted sides would meet.
To sort quadrilaterals, check their angles, their side lengths and their parallel sides.
Curriculum
Where this fits
- British Columbia, Grade 5
Mathematics, Geometry and measurement: classification of prisms and pyramidsBC5-MA-31
Previous: Prisms and pyramids: name it by its baseNext: Translation: Sliding a Shape on a Grid
The outcomes and strands follow the British Columbia curriculum.
Keep going
1 min 12 s3:15 p.m. or 15:15? Morning, afternoon and the 24-hour clock
Grade 4 · 1 min 12 s
1 min 26 s3D Objects: Faces, Edges and Vertices
Grade 3 · 1 min 26 s
1 min 21 sArea and Perimeter: What Is the Difference?
Grade 5 · 1 min 21 s
1 min 5 sArea of a Circle from the Radius or the Diameter
Grade 7 · 1 min 5 s
1 min 14 sArea of a Parallelogram: Cut and Slide into a Rectangle
Grade 6 · 1 min 14 s
1 min 18 sArea of a Rectangle: Count the Squares, Then Multiply
Grade 5 · 1 min 18 s
1 min 16 sArea of a Trapezoid: Two Copies Make a Parallelogram
Grade 6 · 1 min 16 s
1 min 19 sArea of a Triangle: Half of a Parallelogram
Grade 6 · 1 min 19 s
- All Grade 5 Mathematics lessons
- Teachers: the maths worksheets for Grade 5 are in the dashboard, each with a worked example and a proven answer key.
- Try the graph paper, free for everyone, no account needed.
- Create a free account to watch three lessons a day, no payment and no card.