# 1TH/Vwo §3.4 Plotting graphs

§3.4 Plotting graphs
You're going to plot a lot of graphs today!
Finally you will exchange your Notebooks and give points for your neighbour's work.

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Slide 1: Slide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 1

This lesson contains 29 slides, with text slides.

Lesson duration is: 60 min

## Items in this lesson

§3.4 Plotting graphs
You're going to plot a lot of graphs today!
Finally you will exchange your Notebooks and give points for your neighbour's work.

#### Slide 1 -Slide

an interesting exercise ...
we will do together right now!
+ take before you:
a.  Notebook
b.   pen
c.   pencil   and
d.   geo triangle (or ruler), from your bag and pencil case!

#### Slide 2 -Slide

Schermafbeelding 2020-10-12 om 13.27.34

#### Slide 3 -Slide

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:
keep 10 cm open for the VERTICAL axis!

timer
0:45

#### Slide 4 -Slide

22a Above you see how the HORIZONTAL axis is drawn.
Once more: make sure you have about 10 cm for the VERTICAL axis!

#### Slide 5 -Slide

Think it over and compare with your neighbour.
timer
0:45

#### Slide 6 -Slide

10 cm (or grids)  =    put 1 finger up
8 cm  =  put 2 fingers up
12 cm  = put 3 fingers up

#### Slide 7 -Slide

22b
8 cm (or grids) is the right answer,
because 20 cm is the smallest length and
58 cm is the greatest length.
We use numbers like 20, 25, 30  etcetera.
60 cm is nearest to 58 cm.
Then we need at least:        60 - 20 = 40,           40 : 5 = 8 grids.

#### Slide 8 -Slide

Let me be honest.....
The answer, given in the previous slide,
was not quite accurate...
In fact you need (at least) 9 cm and not 8 cm.
The cm extra is for a ZIGZAG, that covers     0 cm  -    20 cm !
Now we do question 22c!

#### Slide 10 -Slide

like the river in the previous slide .....
our activities keep flowing !
Just go with the flow!

S
timer
0:30

#### Slide 12 -Slide

If you think:
variable= kg     and    unit =   weight,    then   raise 2 fingers
variable = weight   and   unit = kg,            then  raise 4 fingers.

#### Slide 13 -Slide

variable = weight
and       unit = kg    (eenheid),
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)!

#### Slide 14 -Slide

So go ahead and draw. Don't forget the ZIGZAG for 0 - 20 kg!
timer
0:45

#### Slide 15 -Slide

In the next slide ....
+ you see the complete graph already
+ but for now it's only about the axes!

#### Slide 17 -Slide

Now do tasks e and f!

timer
0:45

#### Slide 20 -Slide

Rounding off this exercise ...
+  Look critically at your neighbour's graph:
+ is it correct and neat (no crossing out)?  = 1 point
+ did (s)he use a pencil?                                        = 1 point
+ are the axis drawn as straight lines?           = 1 point
+ totalise the points and give back the Notebook
+ if you scored at least 2 points, then the coming JOKE is for you!

#### Slide 22 -Slide

Abov

Above the general way to make a GRAPH from a TABLE is shown!
Next slide gives an example.

#### Slide 24 -Slide

In the GRAPH in the following slide
there is something NEW.            I've got 2 questions about it:
1st What's new?!
2nd What's the great thing you can READ OFF now?

#### Slide 26 -Slide

1st   Two graphs are shown.