SymmetrySymmetry
Line Symmetry
Rotational (Order) Symmetry
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Creating Rotational Symmetry
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Starter QuestionsStarter Questionsw
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Q2. If 1 bar of chocolate costs 65p. How much will1000 bars cost. Give your answer in £’s.
(a) 4.56 (b) 7.254 (c) 9.244
Q3. Round to 1 decimal place
Q4. Covert to 24 hrs clock
(a) Half bast 4 in the af ternoon.
(b) Quarter to eight in the morning.
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Line SymmetryLine Symmetryw
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1.1. Understand the term Understand the term line symmetry.line symmetry.
1. To revise line symmetry.
2.2. Complete Drawings Complete Drawings given the line of given the line of symmetry.symmetry.
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Line SymmetryLine Symmetryw
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A line symmetry occurs in a shape if, when the shape is folded over the line the two pieces either side of the line, are exactly the same.
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Line SymmetryLine SymmetryThe ParallelogramThe Parallelogram
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No lines of symmetry !
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Line SymmetryLine SymmetryThe Equilateral The Equilateral
TriangleTriangle
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Line SymmetryLine SymmetryThe Trapezium 2The Trapezium 2
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No lines of symmetry !
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Line SymmetryLine Symmetryw
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19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.
Now try MIA Ex1Ch3 (page 33)
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Line SymmetryLine Symmetry
Starter QuestionsStarter Questionsw
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Q1. Round the following to the first decimal place.
Q2. What fraction is the green area. What fraction is the grey area.
Q3. A pencil costs 22p. How much doesa 1000 cost. Put your answer in £’s.
(a) 153.37 (b) 261.55
Rotational Rotational SymmetrySymmetry
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1.1. Understand the terms Understand the terms rotational symmetry.rotational symmetry.
1. To explain rotational symmetry for a shape.
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S4Rotational SymmetryRotational Symmetry
This new shape has HALF - TURN symmetry
This dot is called the centre of symmetry
2. Use the tracing paper to make a copy of this shape.
3. Turn the tracing paper through 180 degrees about the dot.
1. Draw this shape into your jotter.
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Rotation SymmetryRotation SymmetryHalf Turn Half Turn
All these shapes have order 2
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Rotation SymmetryRotation SymmetryOrder Order
Has order 2
Has order 3
Has order 4
The order of symmetry is the number of times a shape looks the same in one complete turn.
19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.
Now try MIA Ex2Ch3 (page 36)
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Rotational Rotational SymmetrySymmetry
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30% of £600Q1. Calculate
Q4. Find the perimeter and area of the square.
Q3.
Q2. What is the time difference between 8.15am and 1:00pm
Solve 6y-16 20
Q5. Find the order of rotational symmetry for the shape opposite.
5cm
1
3 2
4
5 6
A=25cm2
P=20cm
Creating Half-TurnCreating Half-TurnSymmetrySymmetry
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Learning IntentionLearning Intention Success CriteriaSuccess Criteria
1.1. Understand the terms Understand the terms half-turn symmetry.half-turn symmetry.
1. To explain how we can create half-turn symmetry for a shape.
2.2. Draw the other half of a Draw the other half of a shape such that it has shape such that it has half-turn symmetry.half-turn symmetry.
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Creating Half-TurnCreating Half-TurnSymmetrySymmetry
Task 1Draw the complete shape you get
after it has been rotatedthrough 180 degrees about the point.
Task 2Do the same for this shape
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Creating Half-TurnCreating Half-TurnSymmetrySymmetry
If you find it difficult to work out the new shape 1. Try tracing the shape first2. Then rotate tracing paper 180 deg about the point.
Task 3Do the same for this shape