4.4 To describe 2-dimensional figures in terms of different

Mathematics

Geometry

Educator section

Memorandum

Learner section

Content

1. Have a class discussion on the properties of each of the figures given above with regard to the following:

(i) Number of sides and lengths

(ii) Number of angles, types of angles and sizes

(iii) Number of vertices

2. Work in groups of three. Choose any two of the above figures, e.g. a rectangle and a parallelogram. Design a poster on which you set out the differences and similarities of the two figures neatly. Display the poster so that the rest of the learners in the class can see it.

Evaluate your work on a scale 1 – 4 by circling the appropriate number:

Let’s do rivision!

• When do we say that a figure is symmetrical?

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• Which of the above figures are symmetrical?

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DID YOU KNOW?

A design that fits into its outlines more than once, has rotational symmetry. The number of times that a design fits into its own outlines is referred to as the order of symmetry.

Assessment

Learning Outcome 3: The learner will be able to use appropriate measuring units, instruments and formulae in a variety of contexts.

Assessment Standard 3.2: We know this when the learner describes and classifies two-dimensional shapes and three-dimensional objects in terms of properties.