Scaled Drawings

1
Scaled Drawings
The Eight Point Compass
Estimating and Drawing Bearings
Working with Scale Drawings
More Scale Drawings
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Directions on Maps
Enlarging and Reducing
Similar Rectangles
2
Starter Questions
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3
Compass Points
4
If Gary walks to John then to Barry and then back
to where he started. Write down all the
directions he took.
If Anne walks to Julie then to Amy and then back
to where she started. Write down all the
directions she took.
If Daniel is facing North and turns clockwise to
face Anne. How many degrees is this.
If Daniel is facing Frances and turns clockwise
to face Amy. How many degrees is this.
If Amy is facing Paul and turns anti-clockwise to
face Daniel. How many degrees is this.
Who is North of Daniel
Who is East of John
Who is South West of Barry
Who is North East of Gary
Compass Points






Frances
John
Barry
N
Daniel
Julie
Anne
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Amy
Gary
Paul
5
Compass Points
Now try Ex 2.1 Ch6 (page 88)
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Starter Questions
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Bearings
Learning Intention
Success Criteria
1. Understand what bearing is.
1. To explain what a bearing is and how to
measure and draw a bearing.
2. Measure and draw a bearing.
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1. Measured from North.
060o
2. In a clockwise direction.
3. Written as 3 figures.
315o
230o
145o
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Bearings
Use your protractor to measure the bearing of
each point from the centre of the circle.
(Worksheet 1)
A 360o protractor is used to measure bearings.
Worksheet 1
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Estimate the bearing of each aircraft from the
centre of the radar screen.
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Scaled Drawings using Bearings
Draw a bearing of (a) 50o (b) 230o
N
N
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50o
230o
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Compass Points
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My Estimated Bearing True Bearing Error
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2
3
4
5
6
7
8
9
10
11
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Total Error
Average Error
My Estimated Bearing True Bearing Error
1
2
3
4
5
6
7
8
9
10
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Total Error
Average Error
Worksheet 2 (Radar)
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Bearings
Now try Ex 3.1 Ch6 (page 90)
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Starter Questions
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Scales
Learning Intention
Success Criteria

1. To understand the term scale.

1. To explain the term scale on a map.
2. Calculate the real life distances using a
scaled map.
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Scales
In order to make sense of a map or scale
diagram the scale must be known.
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Scales
In order to make sense of a map or scale
diagram the scale must be known.
For this scale model
1 cm represents 1m
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4 cm
This means for every 1 metre of the actual car,
1cm is drawn on the map.
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Scales
The scale of this drawing is 1cm 5m
6cm
What is the actual length of the tree ?
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30m
6 x 5
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Scales
The scale of this drawing is 1cm 90cm
What is the actual length of the bus in metres ?
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5cm
450cm
5 x 90
4.5m
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Scales
Now try Ex 4.1 Ch6 (page 92)
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Starter Questions
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Scaled Drawings
Learning Intention
Success Criteria
1. From information given make a scaled drawing.
1. To draw a scale drawing given suitable
information.
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Scaled Drawings
Problem
A garden is rectangular in shape and has length
12m and breadth 8m. Make rough sketch of the
garden.
12m
Draw an accurate scaled drawing of the
garden Use a scale of 1cm represents 2m
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8m
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Scaled Drawings
Use a scale of 1cm represents 2m
1cm represents 2m
12m
12m
8m
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8m
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Scaled Drawings
Problem
A road junction is triangular in shape. A rough
sketch is given below.
Draw an accurate scaled drawing of the
garden Use a scale of 1cm represents 2m
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20m
12m
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Scaled Drawings
Use a scale of 1cm represents 2m
1cm represents 2m
Find the real life length of the 3rd side
20m
20m
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12m
23.2m
2 x 11.6
12m
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Scaled Drawings
Now try Ex 5.1 Ch6 (page 94)
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Starter Questions
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Scaled Drawings using Bearings
Learning Intention
Success Criteria
1. Construct an accurate scale drawing.
1. To explain how to construct a scale drawing
using bearings.
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31
Scaled Drawings using Bearings
Make an accurate scale drawing of this sketch.
N
N
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50o
50o
15km
15km
1cm represents 3km
1cm represents 3km
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Scaled Drawings using Bearings
Make an accurate drawing of the plane journey
N
N
N
N
120o
120o
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45o
45o
8km
12km
12km
8km
1cm represents 2km
1cm represents 2km
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Scaled Drawings using Bearings
Now try Ex 6.1 Ch6 (page 61)
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Starter Questions
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Map Directions
Learning Intention
Success Criteria
1. Be able to make sense of a map.
1. To show how to write down directions using
a map.
2. Write down accurate directions from a map.
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I leave the zoo to go back to my car which is in
the town car park. Write down the directions I
should take.
After going to the park I want to go to the
cinema. Tea Lane is closed. Write down the
directions I should take.
Theres a fire at the library. Right down the
directions the fire engine should take.
I come out of the swimming pool and turn right
then left. I go into the building second on my
the right. Name the building.
I come out of school and go to the Park. Write
down the directions I must take.
I come out of the charity shop and need to catch
a bus. Write down the directions to the bus
station.
Map Directions
N
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37
Map Directions
Now try Ex 7.1 Ch6 (page 97)
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Enlarging Reducing
Learning Intention
Success Criteria
1. Be able to enlarge a shape by a factor of two.
1. To explain how to enlarge or reduce a given
shape by a factor of two or half.
2. Be able to reduce a shape by a factor of a
half.
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Enlarging Reducing
These two photos are of the same view
3cm
1.5cm
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2cm
4cm
The second is double the size of the first.
The first could be ENLARGED to make the second.
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Enlarging Reducing
These two photos are of the same view
3cm
1.5cm
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2cm
4cm
The first is half the size of the second.
The second could be REDUCED to make the first.
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Double the size of the shape.
Enlarging Reducing
Half the size of the shape.
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42
Enlarging Reducing
Now try Ex 8.1 Ch6 (page 99)
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Starter Questions
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Similar Rectangles
Learning Intention
Success Criteria
1. Understand the words similar and factor.
1. To explain the meaning of the word
similar and factor in mathematics. Enlarge
and reduce similar rectangles by a given factor.
2. Be able to enlarge / reduce a rectangle by a
given factor .
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Similar Rectangles
These two rectangles are similar.
4cm
2cm
4cm
8cm
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The first has been ENLARGED by a factor of 2
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Find the missing length ? cm
Similar Rectangles
Find the enlargement factor
These two rectangles are similar.
?cm
2cm
4cm
12cm
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The first has been ENLARGED by a factor of 3
? 2 x 3 6cm
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Find the missing length ? cm
Similar Rectangles
Find the reduction factor
These two rectangles are similar.
8cm
?cm
4cm
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16cm
The first has been ENLARGED by a factor of 4
? 8 4 2cm
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Similar Rectangles
Now try Ex 9.1 Ch6 (page 100)
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