Lesson · Grade 1 · Mathematics
Two Triangles Make a Square
- Grade 1
- Mathematics
- 55 s
- British Columbia
- BC1-MA-17
Two matching triangles are compared and their 3 sides counted, then one is turned like a puzzle piece and the two slide together, long side to long side, to fill an empty square outline. The new square's 4 sides are counted and a stick shows they are all the same length, a sandwich cut corner to corner goes back together the same way, and the video ends on "Two matching triangles can make one square."
Concept: Putting shapes together: two triangles make a square
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In one sentence
The question this lesson answers
Can two triangles make one square? Let's find out.
These two triangles are the same size and shape.
Transcript
What the lesson says
Can two triangles make one square? Let's find out.
These two triangles are the same size and shape.
A triangle has three sides: one, two, three.
Each triangle has one long, slanted side.
Turn one triangle around, like a puzzle piece.
Slide them together, long side to long side.
Look, the two triangles make a square!
The square has four sides: one, two, three, four.
All four sides are the same length.
Two sandwich halves make a square the same way.
Two matching triangles can make one square.
Curriculum
Where this fits
- British Columbia, Grade 1
Mathematics, Geometry and measurement: comparison of 2D shapes and 3D objectsBC1-MA-17
The outcomes and strands follow the British Columbia curriculum.
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