Hong Kong
Stage 1

# Names and Properties of Shapes

Lesson

## Which shape is that?

When we think about shapes, there are some useful clues that tell us what shape we have. We can look at how many sides our shape has, as well as whether or not it has angles, and how many. Some shapes have no angles, but they are still called shapes. Can you think what shapes these are? To be a shape, there must be at least one side, with no gaps!

### Classifying shapes

Some shapes can be classified in more than one way, depending on their features. A square is a particular kind of rectangle, but did you know it is also a polygon (a shape made up of at least $3$3 straight lines), a regular shape (a shape where all sides are the same length, and all angles the same), a parallelogram (a shape with two sets of parallel lines), a quadrilateral (a shape with only $4$4 sides), and a rhombus (a $4$4-sided shape, where all sides are equal in length)? Phew! Squares are pretty impressive shapes.

Let's look at the following shapes in our video, and see how how they are made:

• triangle
• rectangle
• square
• circle
• rhombus
• kite

Careful!

Sometimes, the difference between how we classify shapes relates to how many sides it has, and how they are set out. Other times, it can be because of the angles, or vertices, a shape has. Right angles are a special kind of angle, and can be used to determine some shapes.

#### Worked Examples

##### Question 1

How many sides do each of the following shapes have?

##### Question 2

How many angles are there inside the following shapes?

##### Question 3

Which of the following shapes are rectangles? Choose all correct answers.

1. A

B

C

D