2TH §3.2 Calculating with a scale factor

• Wiskunde
• Middelbare school
• havo, vwo
• Leerjaar 2

§3.2 Calculating with a scale factor

First a refresh on §3.1 !

§4.2 Calculating with a scale factor

THE SCALE FACTORS HERE ARE:

0.5  AND  3.

A RECAP on RATIO TABLES ...

Let us start with §3.2 now!

- open your Notebook and 

- open your Textbook, p.102/103

- get a pen, pencil, geo or ruler ready

- we're going to do a Homework exercise together, 

  this will save you time to do it yourself at home  

- WRITE DOWN IN THE MARGIN: 8a        

Exercise 8

Exercise 8

ANS

Figure ...

1. A
2. B
3. C
4. D

SOLUTION 8a:         B, because the angles are different from A.

Write this in your Notebook!

Now do 8b     

Write down '8b' in the margin and

answer the next slide.

A division for this task could be:

1. 2.5 : 7
2. 4.2 : 1.5
3. 7 : 2.5
4. 1.5 : 4.2

Solution to 8b:   7 : 2.5   and also   4.2 : 1.5

Write this in your Notebook!

Now ..... gets the turn!

What is your answer to 8c?

By the way,  give the scale factor as 

one number!

Let's all write down the Solution in our Notebook:

8c  4.2 : 1.5 = 2.8     or    7 : 2.5 = 2.8

Solutions 8d and 8e:

Homework time 

- Do exercises 9, S10, 10, 11, 12 and 13  (§3.2 Calculating with a scale factor)

  

-  Check with another colour and with the Solutionsbook

- Take a few pics and upload them in Classroom

After this lesson, what question do you still have?