year 8 maths

184 Chapter 3 Measurement and Pythagoras’ theorem
6 A circle’s diameter AC is 15 cm and the chord AB is 9 cm . Angle ABC is 90° . Find the length of
the chord BC .
15 cm
C
A
9 cm
B
7 A 14 cm drinking straw just fits into a can, as shown. The diameter of the can is 7 cm . Find the height
of the can, correct to two decimal places.
14 cm
7 cm
8 Find the length AB in this diagram. Round to two decimal places.
25
11
24 A B
9 Describe what is wrong with the second line of working in each step.
a a 2 + 10 = 24
a 2 = 34
b a 2 = 25
= 5
c a 2 + 25 = 36
a 2 + 5 = 6
10 The number √11 is an example of a surd that is written as an exact value. Find the surd that
describes the exact lengths of the unknown sides of these triangles.
a 5
b
c 100
7
2
120
1
Cambridge Maths NSW
Stage 4 Year 8 Second edition
ISBN 978-1-108-46627-1 © Palmer et al. 2018
Cambridge University Press
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