1. Using the right words – the language of shapes
Each slide has one or more shapes and description(s).
The help you learn and pronounce the words, click on the audio to play the commentary.

2. Contents – click to jump to the page
Equilateral triangle
Isosceles triangle
Scalene triangle
Right triangle
Obtuse triangle
Acute triangle
Congruence
The parts of 3-D shapes
Prisms – hexagonal prism
More about prisms
Some other 3-D shapes

3. Equilateral triangle
All three sides equal
All three angles equal

4. Isosceles triangle
Two equal sides
Two equal angles

5. Scalene triangle
No equal sides
No equal angles

6. The two sides next to the right angle
may or may not be
equal
One angle of 90o
Other angles may or may not be equal
Right triangle (sometimes called a Right angled triangle)

7. One angle greater than
90o
Obtuse triangle

8. All angles less than
90o
Acute triangle

9. A B A B A B “Congruent” – means “the same as” 𝑨 ≅𝑩 Congruent lines
Lines, angles, circles and polygons can all have congruence. A
Congruent lines
Congruent triangles A B B
Congruent angles A
Congruent circles B
Congruent means equal in size and shape but not necessarily in orientation or position

10. The parts of three dimensional shapes
Face – the surface of the shape. This shape has 6 faces.
Vertex (for one) or vertices (for more than one) – where the edges of the shape meet, this shape has 8 vertices
Edge – where two faces join. This shape has 12 edges.
The parts of three dimensional shapes

11. Prisms Prisms are named for the shape of their bases
This is a hexagonal prism
Prisms

12. This is a rectangular prism
A cube is a special type of rectangular prism where all faces are squares
A triangular prism has bases that are triangles
More about prisms

13. Other three dimensional shapes
A cylinder has two parallel congruent circular faces.
Apex
A pyramid has one polygonal base (not necessarily square) and lateral triangular faces that meet at a common vertex called the apex.
A cone is similar to a pyramid but has a circular base and so only one curved face.
A sphere is made up of all the points in space that are the same fixed distance from its centre.
Other three dimensional shapes

14. Using the right words – the language of shapes
THE END