Symmetry Line Symmetry Rotational (Order) Symmetry MTH 2-19a MTH 3-19a Line Symmetry Rotational (Order) Symmetry Creating Rotational Symmetry www.mathsrevision.com Translational Symmetry
Starter Questions www.mathsrevision.com Q1. Calculate MTH 2-19a MTH 3-19a Q1. Calculate Q2. If 1 bar of chocolate costs 65p. How much will 1000 bars cost. Give your answer in £’s. Q3. Round to 1 decimal place www.mathsrevision.com Q4. Convert to 24 hrs clock
Line Symmetry www.mathsrevision.com Learning Intention MTH 2-19a MTH 3-19a Learning Intention Success Criteria To revise line symmetry. Understand the term line symmetry. Complete Drawings given the line of symmetry. www.mathsrevision.com
Line Symmetry www.mathsrevision.com MTH 2-19a MTH 3-19a 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. www.mathsrevision.com
Line Symmetry The Square MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry The rectangle MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry The square MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry The Rhombus MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry The Parallelogram MTH 2-19a MTH 3-19a www.mathsrevision.com No lines of symmetry !
Line Symmetry The Equilateral Triangle MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry The Trapezium 1 MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry The Trapezium 2 MTH 2-19a MTH 3-19a No lines of symmetry ! www.mathsrevision.com
Line Symmetry The Hexagonal MTH 2-19a MTH 3-19a www.mathsrevision.com
Line Symmetry www.mathsrevision.com MTH 2-19a MTH 3-19a Example : Complete the rest of the shape given the line of symmetry. www.mathsrevision.com
Creating Half-Turn Symmetry MTH 2-19a MTH 3-19a Your turn ! Exercise 1 Page 81 www.mathsrevision.com
Starter Questions www.mathsrevision.com MTH 2-19a MTH 3-19a Q1. Round the following to the first decimal place. (a) 153.37 (b) 261.55 Q2. What fraction is the green area. What fraction is the grey area. www.mathsrevision.com Q3. A pencil costs 22p. How much does a 1000 cost. Put your answer in £’s.
Rotational Symmetry www.mathsrevision.com Learning Intention MTH 2-19a MTH 3-19a Learning Intention Success Criteria We are learning what rotational symmetry is for a shape. Understand the terms rotational symmetry. www.mathsrevision.com
Rotational Symmetry www.mathsrevision.com MTH 2-19a MTH 3-19a 1. Draw this shape into your jotter. 2. Use the tracing paper to make a copy of this shape. 3. Turn the tracing paper through 180 degrees about the dot. www.mathsrevision.com This new shape has HALF - TURN symmetry This dot is called the centre of symmetry
Rotation Symmetry Half Turn MTH 2-19a MTH 3-19a www.mathsrevision.com All these shapes have order 2
Rotation Symmetry Order MTH 2-19a MTH 3-19a The order of symmetry is the number of times a shape looks the same in one complete turn. Has order 2 www.mathsrevision.com Has order 3 Has order 4
Your turn ! Exercise 2 Page 82 Rotational Symmetry MTH 2-19a MTH 3-19a Your turn ! Exercise 2 Page 82 www.mathsrevision.com
Starter Questions www.mathsrevision.com Q1. Calculate MTH 2-19a MTH 3-19a Q1. Calculate Q2. What is the time difference between 8.15am and 1:00pm P=20cm Q3. A=25cm2 www.mathsrevision.com 5cm Q4. Find the perimeter and area of the square. Q5. Find the order of rotational symmetry for the shape opposite. 5 6 1 4 3 2
Creating Half-Turn Symmetry MTH 2-19a MTH 3-19a Learning Intention Success Criteria We are learning how we can create half-turn symmetry for a shape. Understand the terms half-turn symmetry. Draw the other half of a shape such that it has half-turn symmetry. www.mathsrevision.com
Creating Half-Turn Symmetry MTH 2-19a MTH 3-19a Task 1 Draw the complete shape you get after it has been rotated through 180 degrees about the point. Task 2 Do the same for this shape www.mathsrevision.com
Creating Half-Turn Symmetry MTH 2-19a MTH 3-19a Task 3 Do the same for this shape www.mathsrevision.com If you find it difficult to work out the new shape 1. Try tracing the shape first 2. Then rotate tracing paper 180 deg about the point.
Creating Half-Turn Symmetry MTH 2-19a MTH 3-19a Your turn ! Exercise 3 Page 85 www.mathsrevision.com
Starter Questions www.mathsrevision.com Q1. Calculate MTH 2-19a MTH 3-19a Q1. Calculate Q2. What is the time difference between 8.15am and 1:00pm Q3. www.mathsrevision.com Q4. (-2) + (-3) Q5. How many lines of symmetry does regular hexagon have.
Translational (slide) Symmetry MTH 2-19a MTH 3-19a Learning Intention Success Criteria We are learning the meaning of Translational (slide) symmetry using tile patterns. Understand the terms translational, slide congruent and tile. www.mathsrevision.com Identify shapes that tile. Construct a tile pattern for shapes.
Translational (slide) Symmetry MTH 2-19a MTH 3-19a Exactly the same shape and size ! www.mathsrevision.com A shape that tiles can be completely surrounded by congruent shapes WITHOUT leaving any gaps.
Translational (slide) Symmetry MTH 2-19a MTH 3-19a Is this a tile pattern ? No because there are gaps www.mathsrevision.com
Translational (slide) Symmetry MTH 2-19a MTH 3-19a Write down as many tile patterns as you can that you see every day. www.mathsrevision.com
Translational (slide) Symmetry MTH 2-19a MTH 3-19a Your turn ! Exercise 4 Page 87 www.mathsrevision.com