year 8 maths

NSW syllabus
STRAND: NUMBER AND ALGEBRA
SUBSTRAND: EQUATIONS
Outcome
A student uses algebraic techniques
to solve simple linear and quadratic
equations.
(MA4–10NA)
© NESA, 2012
Protecting sea turtles
Loggerhead sea turtles are magnificent marine predators that feed on shellfish, crabs, sea
urchins and jellyfish. Sadly, Australian loggerhead turtles have lost more than 50% of their
nesting females in the past 10 years. These diminishing numbers mean that loggerhead turtles
are now an endangered species. They are under threat for a number of reasons, including
human activity on the beaches where the females lay eggs and accidental death in fishing
nets. In order to work out how to best save the loggerhead sea turtle, scientists need to work
out what effect various actions, such as closing beaches, will have on the loggerhead
turtle population.
To do this scientists use mathematics! With a combination of data and equations, they use
computer models to predict population numbers of future generations of the loggerhead turtle.
For example, this simple equation describes the number of turtles that there will be next year:
F = C(1 + B − D)
The pronumerals used in this equation are:
• F = future population
• C = current population
• B = birth rate
• D = death rate
By mathematically predicting the future of the loggerhead turtle population, environmental
scientists can advise governments of the best decisions to help save the loggerhead sea
turtle from extinction.
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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