1TH/Vwo §3.4 Plotting graphs

• Wiskunde
• Middelbare school
• havo, vwo
• Leerjaar 1

A good look back at §3.3 first!

OPEN YOUR NOTEBOOK and 

SHOW ME:            EXERCISES 20 and 21

I will have a look at your work and 

we will go through the content (= inhoud) soon.

§3.4 Plotting graphs

You're going to plot (= draw) a few graphs today!

By the way, your ipad stays in the bag, as you don't need it for this Lessonup!

an interesting exercise ...  

                  we will do soon!

+ take before you:            

      a.  Notebook

      b.   pen

      c.   pencil   and

      d.   geo triangle (or ruler), from your bag and pencil case!

an interesting exercise ...  

                  we will do soon!

First the METHOD for making good graphs is shown!  

It's a lot of information.

Don't worry about it, but

- try to follow it as good as you can

- make the tasks that follows and 

- after this you will see the METHOD once more 

Abov

Above the general way to make a GRAPH from a TABLE is shown!

Next slide gives an example.

Schermafbeelding 2020-10-12 om 13.27.34

Schermafbeelding 2020-10-12 om 13.27.55

 DRAW the HORIZONTAL axis.     

USE A PENCIL and a PENCIL ONLY !!!   (the numbers and words may be written with a pen)

Look at the lowest age in the table:  it is 6 years.

So: start your horizontal axis at 6 years!  See next slide.

However: 

               take 10 cm for the VERTICAL axis!

22a Below you see how the HORIZONTAL axis is drawn.

Once more: make sure you have about 10 cm for the VERTICAL axis!

Think it over and compare your idea with your neighbor.

Answer 22b:

Because of two reasons:

1st:    the numbers 0 to 20 you don't need in the graph.

2nd:  steps of 5 make sure that your graph doesn't get too high!

       To be concrete: if you use 1 cm for 1 kg, then your vertical axis will be

       about 60 cm high!!

like the river in the previous slide .....

our activities keep flowing !

Just go with the flow!

S

Answer to 22c:

If you think:

variable= kg     and    unit =   weight,    

          then   raise 2 fingers

variable = weight   and   unit = kg,           

           then  raise 4 fingers.

Answer and Explanation 22c:

variable = weight

and       unit (eenheid) = kg    ,

so 4 FINGERS was correct!

A VARIABLE (something that changes over time, in this case weight) 

is expressed in a UNIT (in this case kg)!

     So go ahead and draw. Don't forget the ZIGZAG for 0 - 20 kg!

In the next slide ....

+ you see the complete graph already

+ but for now it's only about the axes! 

Now do tasks e and f!

In the next slide you see the whole task again!

Abov

Above the general way to make a GRAPH from a TABLE is shown!

Next slide gives an example.

TASK:

In the GRAPH in the following slide

there is something NEW.            I've got 2 questions about it:

1st What's new?! 

 2nd What is the great thing about this ? 

          In other words: what can you do, having two graphs in one coordinate system?

Discuss this with your neighbor!

Answer:

1st   Two graphs are shown.

2nd  The great thing about this is that you can

COMPARE (vergelijken) them!!     

Homework time

Do:

§3.4 Plotting graphs, you may SKIP 22 and 23.