1. Compiled by Mr. Lafferty Maths Dept.
Pythagoras Theorem
Calculating the Hypotenuse
Solving real-life problems
Finding the length of the smaller side
Mixed Problems
Distance between two points
Exam Type Questions
17-May-18
Compiled by Mr. Lafferty Maths Dept.

2. Compiled by Mr. Lafferty Maths Dept.
Starter Questions
17-May-18
Compiled by Mr. Lafferty Maths Dept.

3. Calculating Hypotenuse
Learning Intention
Success Criteria
We are learning to use Pythagoras Theorem to calculate the length of the hypotenuse
“the longest side”
Remember the term hypotenuse “ the longest side”
Apply Pythagoras Theorem to calculate the hypotenuse.
17-May-18
Compiled by Mr. Lafferty Maths Dept.

4. Calculating the Hypotenuse
Level 4
Example 1
Calculate the longest length of the right- angled triangle below. c 8 12
17-May-18
Compiled by Mr. Lafferty Maths Dept.

5. Calculating the Hypotenuse
Level 4
Example 2
An aeroplane is preparing to land at Glasgow Airport. It is over Lennoxtown at present which is 15km from the airport. It is at a height of 8km.
How far away is the plane from the airport?
Aeroplane c
b = 8
Airport
a = 15
Lennoxtown
17-May-18
Compiled by Mr. Lafferty Maths Dept.

6. Calculating Hypotenuse
Now try TJ4+
Ex 13.1
Ch13 (page 92)
17-May-18
Compiled by Mr. Lafferty Maths Dept.

7. Compiled by Mr. Lafferty Maths Dept.
Starter Questions
17-May-18
Compiled by Mr. Lafferty Maths Dept.

8. Solving Real-Life Problems
Learning Intention
Success Criteria
1. We are learning how Pythagoras Theorem can be used to solve real-life problems.
Be able to solve real-life problems using Pythagoras Theorem showing clear working.
17-May-18
Compiled by Mr. Lafferty Maths Dept.

9. Solving Real-Life Problems
When coming across a problem involving finding a missing side in a right-angled triangle, you should consider using Pythagoras’ Theorem to calculate its length.
Example : A steel rod is used to support a tree
which is in danger of falling down.
What is the length of the rod?
15m 8m
rod
17-May-18
Compiled by Mr. Lafferty Maths Dept.

10. Solving Real-Life Problems
Example 2
A garden is rectangular in shape. A fence is to be put along the diagonal as shown below.
What is the length of the fence.
10m
15m
17-May-18
Compiled by Mr. Lafferty Maths Dept.

11. Solving Real-Life Problems
Now try TJ4+
Ex 13.2
Ch13 (page 94)
17-May-18
Compiled by Mr. Lafferty Maths Dept.

12. Compiled by Mr. Lafferty Maths Dept.
Starter Questions
17-May-18
Compiled by Mr. Lafferty Maths Dept.

13. Length of the smaller side
Learning Intention
Success Criteria
1. We are learning how Pythagoras Theorem can be used to find the length of the smaller side.
Apply Pythagoras Theorem to find the length of smaller side showing clear working.
17-May-18
Compiled by Mr. Lafferty Maths Dept.

14. Length of the smaller side
To find the length of the smaller side of a right- angled
triangle we simply rearrange Pythagoras Theorem.
Example : Find the length of side a ?
Check answer ! Always smaller than hypotenuse
20cm
12cm
a cm
17-May-18
Compiled by Mr. Lafferty Maths Dept.

15. Length of the smaller side
Example : Find the length of side b ?
10cm
b cm
8 cm
Check answer ! Always smaller than hypotenuse
17-May-18
Compiled by Mr. Lafferty Maths Dept.

16. Compiled by Mr. Lafferty Maths Dept.
Length of smaller side
Now try TJ4+
Ex 13.3
Ch13 (page 96)
17-May-18
Compiled by Mr. Lafferty Maths Dept.

17. Compiled by Mr. Lafferty Maths Dept.
Starter Questions
17-May-18
Compiled by Mr. Lafferty Maths Dept.

18. Compiled by Mr. Lafferty Maths Dept.
Pythagoras Theorem
Finding hypotenuse c
Finding
shorter side b c b a
Finding shorter side a
17-May-18
Compiled by Mr. Lafferty Maths Dept.

19. A rectangular metal grill for a window is shown below.
Two diagonal metal bars strengthen the grill.
Find the length of one of the metal bars.
17-May-18

20. A steel plate in the shape of an isosceles triangle is used to strengthen a bridge.
Calculate the height of the steel plate. Do not use a scale drawing.
1.2 m
height
3.6 m
17-May-18

21. Compiled by Mr. Lafferty Maths Dept.
Pythagoras Theorem
Now try TJ4+
Ex 13.4
Ch13 (page 97)
17-May-18
Compiled by Mr. Lafferty Maths Dept.

22. Starter Questions

23. Compiled by Mr. Lafferty Maths Dept.
Finding the
Length of a Line
Learning Intention
Success Criteria
1. We are learning how Pythagoras Theorem can be used to find the length of a line.
Apply Pythagoras Theorem to find length of a line.
2. Show all working.
17-May-18
Compiled by Mr. Lafferty Maths Dept.

24. Finding the Length of a Line 8 (7,7) 7 6 3 5 5 4 (2,4)
Discuss with your partner how we might find the length of the line.
17-May-18
Created by Mr. Lafferty Maths Dept.
Finding the
Length of a Line
Level 4 8
(7,7) 7 6 3 5 5 4
(2,4) 3 2 1 1 2 3 4 5 6 7 8 9 10

25. Pythagoras Theorem to find the length of a Line
17-May-18
Pythagoras Theorem to find the length of a Line
Created by Mr. Lafferty Maths Dept.
Level 4 8 7
(0,6) 6 5 4 5 3 2
(9,1) 9 1 1 2 3 4 5 6 7 8 9 10

26. Pythagoras Theorem Now try TJ4+ Ex 13.5 Ch13 (page 99)
Have you updated your Learning Log ?
Pythagoras Theorem
Now try TJ4+
Ex 13.5
Ch13 (page 99)
17-May-18
Compiled by Mr. Lafferty Maths Dept.

35. 4 marks