# 1TH/vwo §8.2 Adding negative numbers

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Slide 1: Tekstslide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 1

In deze les zitten 38 slides, met interactieve quizzen en tekstslides.

Lesduur is: 30 min

## Onderdelen in deze les

#### Slide 2 -Tekstslide

12   t/m   16
LEARNING GOAL:
How to add NEGATIVE NUMBERS together

#### Slide 3 -Tekstslide

We're gonna do some adding ...
with Positive and especially Negative Numbers!

#### Slide 4 -Tekstslide

As usual...
this LessonUp marches through the most
important aspects of the whole paragraph,
making it much easier to deal with it yourself, afterwards!
We're gonna do several exercises together, so: less homework.

#### Slide 5 -Tekstslide

A special role is reserved today for a peculiar, be it somewhat creepy, person: A Witch!

#### Slide 6 -Tekstslide

The witch is toying with her
HOT BLOCKS and COLD BLOCKS!

#### Slide 7 -Tekstslide

How does this work?!           Like this:

#### Slide 8 -Tekstslide

The witch has a cauldron. (=kettle)
You better not taste one of her brews (brouwsels)...
+ she puts in HOT BLOCKS and also
+ COLD BLOCKS
+ to control the temperature
+ every Blocks represents one degree!

#### Slide 9 -Tekstslide

The temperature is 0 degrees.
The witch adds 5 cold blocks. (1 block = 1 degree)
What's the new temperature?
A
5 degrees
B
+5 degrees
C
-5 degrees
D
0 degrees

#### Slide 10 -Quizvraag

There are 13 cold blocks and 7 hot blocks in the cauldron.
What is the temperature?
A
-6 degrees
B
6 degrees
C
20 degrees
D
-20 degrees

#### Slide 11 -Quizvraag

Explanation:
13 cold blocks correspond to -13 degrees
7 hot blocks correspond to +7 degrees,
so the calculation is:
-13 + 7 = -6

#### Slide 12 -Tekstslide

In the next slide...
+ many changes in temperature come up!
+ your teacher will tackle the first line
+ then all think about the next line
+ one of you will get the turn!
+ and so on with the 3rd line, etcetera

#### Slide 14 -Tekstslide

That may all be true, but ...
it's high time for a Joke!

#### Slide 17 -Tekstslide

What's this?!
Do I see a '+' and a '-' in a row?
Yes, you do. The '+' is for 'adding' and the '-' is for the negative number: '-7'.

#### Slide 19 -Tekstslide

Next slide ...
+ offers us a huge table again
+ your teacher will take care of the first line again
+ then some of you get the turn to tackle the next lines
+ maybe youthink it's all still very simple(?)
+ beware: next lesson the Witch will also TAKE OUT Hot en Cold Blocks;
+ so it's important to understand the ADDING of Blocks first!

#### Slide 21 -Tekstslide

Not really surprising, this, but good to realise!

#### Slide 22 -Tekstslide

Key it in, in the next slide!

Solution:
-35 + 40 = 5

timer
0:30
-6 + .... = -9

#### Slide 26 -Woordweb

-6 + .... =  -9
What to fill in here?

#### Slide 27 -Tekstslide

-6 + ...... = -9
The number to be filled in is:
-3 !
At last ... a JOKE!

#### Slide 29 -Tekstslide

Finally:

An example of this follows!

#### Slide 30 -Tekstslide

What all this?!?
Negative numbers and Fractions too!
This is too difficult for me, Mr. Hauwert!
Okay, next slide shows you a fine way to tackle such ones!

VWO only

1352
timer
1:20
+ ... = -2.5

#### Slide 34 -Woordweb

VWO only
Using the number line, you see that you have to
add up the length from 13        till 0,
and the length from 0 to -2.5 !
That is:   13       +   2         =     15

However we go from positief to negative,
so we subtract. The answer is:  -15.9
52
52
105
109

#### Slide 35 -Tekstslide

Homework time
We skip a lot of tasks.
Make:       12, 13, 14, 15, 16. plus
C3 + C4  A little more about the Challenge tasks follow                       later.

and send them in in GC.

#### Slide 36 -Tekstslide

TIP 1:
in order to make the Graph, first make a TABLE!
Taking the three numbers. 0, 4 and 8 for 'number of buttons' is enough.
(The Solutionsbook takes many more...)

#### Slide 37 -Tekstslide

Feel free to make this task