year 8 maths

6F
Line symmetry and rotational symmetry
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Example 9
Finding the symmetry of shapes
Give the number of lines of symmetry and the order of rotational symmetry for each of these shapes.
a rectangle b regular pentagon
SOLUTION
a
2 lines of symmetry
EXPLANATION
rotational symmetry:
order 2
b 5 lines of symmetry
rotational symmetry:
order 5
Exercise 6F
UNDERSTANDING AND FLUENCY
1–8 2–8
4–8
1 How many ways could you fold each of these shapes in half so that the two halves match exactly?
(To help you solve this problem, try cutting out the shapes and folding them.)
a square
b rectangle
c equilateral triangle
d isosceles triangle
e rhombus
f parallelogram
2 For the shapes listed in Question 1 , imagine rotating them 360° about their centre. How
many times do you make an exact copy of the shape in its original position?
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Cambridge Maths NSW
Stage 4 Year 8 Second edition
ISBN 978-1-108-46627-1 © Palmer et al. 2018
Cambridge University Press
Photocopying is restricted under law and this material must not be transferred to another party.
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