# Negative scale factors

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## Lesson details

### Key learning points

1. In this lesson, we will learn about negative scale factors and explore the commutativity of multiplication.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

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## Worksheet

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## Starter quiz

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### 8 Questions

Q1.
Fill in the gap: Multiplication when viewed as scaling can be thought of as a ___________.
multiplication
scale factor
scaling
Correct answer: stretch
Q2.
Fill in the gap: Looking at the diagram below we can use a ___________ to describe how much the number was scaled by.
multiplication
Correct answer: scale factor
scaling
stretch
Q3.
Fill in the gap: In the diagram below the top arrow can be visualised as stretching -10 by a scale factor of_____.
-10
-3
-30
Correct answer: 3
Q4.
Calculate the following product: 9 x (-12)
Correct answer: -108
-112
108
92
Q5.
Calculate the following product: 0.5 x (-12)
-24
Correct answer: -6
24
6
Q6.
Which calculation best represents the unlabelled arrow?
2 x (-5) = -10
Correct answer: 3 x (-5) = -15
4 x (-5) = -20
6 x (-5) = -30
Q7.
Which calculation best represents the unlabelled arrow.
Correct answer: 0.5 x (-5) = -2.5
1 x (-5) = -5
3 x (-5) = -15
None of the above
Q8.
Calculate: 3 x (-2) + 7 x (-3) - (-27)
-15
-30
Correct answer: 0
27

## Exit quiz

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### 7 Questions

Q1.
Which set of words fill in the gaps in order best? Multiplication by a negative _____________ can be visualised as a _________ in the _____________ direction.
scalar, swing, other
Correct answer: scale factor, stretch, oppositie
scale factor, stretch, positive right
scales, pull, opposite
Q2.
Select the calculation that the red arrow represents in relation to the given arrow of 5 and state the scale factor
Correct answer: (-3) x 5 = -15 s.f: -3
(-3) x 5 = -15 s.f: -5
3 x 5 = 15 s.f: 3
3 x 5 = 15 s.f: 5
Q3.
Which number completes the calculation: ____ x 7 = -21
-28
Correct answer: -3
28
3
Q4.
Which number completes the calculation: (-5) x 2 = (-30) + ____
-10
-20
10
Correct answer: 20
Q5.
Calculate 7 x (-2)
Correct answer: -14
-9
14
5
9
Q6.
Calculate 7 x (-1/2)
-14
Correct answer: -3.5
14
3.5
Q7.
2 + (-4) x 3 =
Correct answer: -10
-18
-24
-6