Teach GCSE Maths Lines: parallel and perpendicular.
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Transcript of Teach GCSE Maths Lines: parallel and perpendicular.
![Page 1: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/1.jpg)
Teach GCSE Maths
Lines:parallel and
perpendicular
![Page 2: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/2.jpg)
Teach GCSE Maths
Lines: parallel and Lines: parallel and perpendicularperpendicular
© Christine Crisp
"Certain images and/or photos on this presentation are the copyrighted property of JupiterImages and are being used with permission under license. These images and/or photos may not be copied or downloaded without permission from JupiterImages"
![Page 3: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/3.jpg)
We use one, two, or sometimes three pairs of arrows to mark parallel lines.
Parallel lines NEVER meet . . . however far we draw
them.
These lines are parallel.
A
B
C
D
We can write AB CD
“AB is parallel to CD”
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A
B
CD
Another line may cross the parallel lines.
Transverse
![Page 5: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/5.jpg)
These angles . . .
are called opposite angles.
Can you see why opposite angles are equal?
a a
ANS: Each is 180 b because of the straight lines.
b
When lines cross we get angles.
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a a b 180
These angles . . .
are called opposite angles.
Can you see why opposite angles are equal?
ANS: Each is 180 b because of the straight lines.
When lines cross we get angles.
![Page 7: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/7.jpg)
a a b 180
These angles . . .
are called opposite angles.
Can you see why opposite angles are equal?
ANS: Each is 180 b because of the straight lines.
When lines cross we get angles.
![Page 8: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/8.jpg)
The angle between them is 90
These lines are perpendicular.
![Page 9: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/9.jpg)
This line has letters at each end.
The full name for AB is a line segment.
A B
A line segment has a start and an end so it has a certain length.
We often refer to line segments as lines but you need to know what is meant if you do meet the full name.
![Page 10: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/10.jpg)
SUMMARYLine
s
a a
Opposite angles are equal.
Lines at 90 are perpendicular.
A line segment has a start and an end so it has a certain length.
Parallel lines NEVER meet.
transverse
Parallel
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Exercise1. Find a line
(a) parallel to AB (b) perpendicular to EF
A
G
B
H
D
J
I
E
C F
K
Answers:
![Page 12: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/12.jpg)
A
G
B
H
J
I
E
C F
K
(a) AB GH
D
Exercise1. Find a line
(a) parallel to AB (b) perpendicular to EF Answers:
![Page 13: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/13.jpg)
A
G
B
H
J
I
E
C F
K
(a) AB GH
D
Exercise1. Find a line
(a) parallel to AB (b) perpendicular to EF Answers:
(b) IJ is perpendicular to EF
![Page 14: Teach GCSE Maths Lines: parallel and perpendicular.](https://reader036.fdocuments.in/reader036/viewer/2022062320/56649d0a5503460f949dcd97/html5/thumbnails/14.jpg)