Calculating in right angled triangles chapter 8

• Wiskunde
• Middelbare school
• havo
• Leerjaar 3

7-5 Calculating in 

right angled triangles

What you need:

- Textbook, writingbook, iPad

- Pen, pencil, geotriangle

- Calculator

Lesson goals

- Nothing new :-) 

We are going to practice calculating unknown sides and angles using

* trigonometry and

* pythagoras

26 (p18)

BC=?

1. 4,2
2. 3,1
3. 5
4. 5,8

EF=?

1. 2,5
2. 2,7
3. 3
4. 4,5

LM=?

1. 5
2. 5,2
3. 5,8
4. 6,3

QR=?

1. 4,5
2. 5
3. 5,6
4. 7,3

YZ=?

1. 7,2
2. 8,1
3. 9,3
4. 10

IG=?

1. 1
2. 2
3. 3
4. 4

27 (p 19)

27a=?

1. 4.2
2. 5.2
3. 5.8
4. 6.0

27b=?

1. 41
2. 43
3. 45
4. 47

27c=?

1. 4,2
2. 5,2
3. 6,1
4. 6,5

27d=?

1. 7,2
2. 8,2
3. 8.9
4. 9,1

27e=?

1. 68
2. 79
3. 81
4. 132

What if we dont have a 90 degree angle?

28 (p. 19)

28c=?

1. 22.5
2. 23
3. 23.5
4. 24

28d=?

1. 25.2
2. 25.3
3. 26.8
4. 27.3

28e=?

1. 13.0
2. 14.0
3. 15.0
4. 16.0

28f=?

1. 36.3
2. 39.8
3. 41.0
4. 41.4

Try on your own

1, 2, 5 and 7

TRY ON YOUR OWN...

RULES:

• In your writingbook
• Use: Textbook
• Discussion when you are stuck is allowed

Extra excercise: none

Challenge: none

25, 29, 30

(p. 18)