Polygon activity 3 decomposition and composition 2/2

Every student chooses two differently coloured papers from the fan.

Questions for Discussion:
What kind of polygon is the square you have?

Questions for Discussion:
What kind of polygon is the square you have?

Folding Instruction:
Fold one corner to lie on top of the non-adjacent corner (opposite corner).  Repeat with the other square.

Question for Discussion:
After the folding, what is the name of the polygon you have made?
Can you describe it?

Answer:
We have a triangle.  The polygon has three vertices and three sides.  Two sides are equal and one angle is a right angle, so the triangle is a ‘right angled isosceles triangle’.

Question for Discussion:
How many different polygons can you make by putting together the two triangles, so that two sides of the same length will always touch?

Answer:
Two triangles will make:

• A parallelogram
  – A square
  – A big triangle

Question for Discussion:
Fold one vertex to lie on top of the other, then open the paper to a square.

Question for Discussion:
How many congruent triangles can you see in the square?

Answer:
The square has four big congruent triangles and four small congruent triangles.

Question for Discussion:
What kind of triangles do you find in the square?

Answer:
All the triangles are right angled isosceles triangles.

Folding Instruction:
Fold two opposite corners of the square to the red dot where the two diagonals intersect.

Question for Discussion:
What kind of polygons can you see?

Answer:
The paper shape is a hexagon.  Inside the hexagon we can find:
– 2 squares
– 2 isosceles
– trapeziums
– 2 pentagons
– 4 right-angled trapeziums

Folding Instruction:
Fold one side to lie on top of the parallel side.

Question for Discussion:
What kind of polygon can you see?  Describe it.

Answer:
The polygon is a quadrilateral called an isosceles trapezium.  Two sides are parallel.

Folding Instruction:
With a marker pen, mark the two short sides of the trapezium and the line of symmetry.

Folding Instruction:
Fold each of the short sides so that they lie partly along the line of symmetry.

Folding Instruction:
Fold in the two corners, part-way to the line of symmetry.

Folding Instruction:
Turn over the paper to the other side.

Question for Discussion:
What are the polygons?

Answer:
– 1 hexagon
– 2 quadrilaterals

Folding Instruction:
Use your markers to draw the face of a rabbit.

Folding Instruction:
Take one of your folded triangles and make two more folds as you want.

Folding Instruction:
Open the paper and with your paper ruler (straight edge), go over the lines with a marker pen.

Folding Instruction:
Look at the polygons in the paper.  Write inside each polygon the name of the polygon.