1TH/vwo §6.4 Formulas from graphs 1st Form (short version)

§6.4 Making a FORMULA from a GRAPH
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Slide 1: Tekstslide
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In deze les zitten 26 slides, met interactieve quizzen en tekstslides.

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§6.4 Making a FORMULA from a GRAPH

Slide 1 - Tekstslide

For this graph...

Slide 2 - Tekstslide

... we cannot make a formula, sadly enough.

Slide 3 - Tekstslide

A STRAIGHT LINE = our type of graph!
Look at the following slide. For this Graph we CAN
make a Formula!  Reason to be happy!

Slide 4 - Tekstslide

Example 1

Slide 5 - Tekstslide

For wat kind of Graph CAN we make a Formula ?
A
a graph that goes up and down
B
a linear graph
C
a graph that has the form of a circle
D
a straight line, that is not vertical

Slide 6 - Quizvraag

Example 1
You will LEARN how to
make a FORMULA for
a graph like this!
First I show you the
general METHOD. 

Slide 7 - Tekstslide

Slide 8 - Tekstslide

Maybe this Theory doen't explain much to you...
That's  why a few EXAMPLES follow.
One about a RISING GRAPH and one about a 
FALLING GRAPH.   


Slide 9 - Tekstslide

Slide 10 - Tekstslide

Example 2: As you see, we have a falling graph here.
Let's call the horizontal axis a and the vertical axis b.

Slide 11 - Tekstslide

Step 1.   Above you see the table with 3 points from the graph.
Let's call the horizontal axis a and the vertical one b.
Step 2.  The graph starts at height 5 on the vertical axis. So that's the starting value.
Step 3.  When the graph goes to the right 1 step, it goes down 2 steps.
Step 4.   Putting steps 2 and 3 in the shape of a Formula:   
                 a x -2 + 5 = b         or         also:            b = -2 x a + 5 
Let us Study the Theory one more time!
            
a
0
1
2
b
5
3
1

Slide 12 - Tekstslide

Slide 13 - Tekstslide

Slides 14 t/m 19 we skip for now.

Slide 14 - Tekstslide

TASK:
Make a FORMULA for the GRAPH on the next slide.
Get a pen, pencil and geo and open your Notebook.
Use the METHOD you just saw.    Two TIPS:
1st        Forgotten all about it?
              It's on p.216 in your Textbook!
2nd      The number that you calculate in step 3 this time is a FRACTION!  
              Apparently Charlie Brown and Lucie are not impressed.  I hope YOU are!   

Slide 15 - Tekstslide

To make this task more interesting ....
Let's make it a FOTOVRAAG!                
So 
* make it
* take a picture and
* send this in in Lessonup!

Slide 16 - Tekstslide

timer
2:50

Slide 17 - Tekstslide

This is MY SOLUTION, take it or leave it.

Slide 18 - Open vraag

step 1.Above you see the Table, 
that contains 3 points from the graph.
Let's call the axes:         a and b.
step 2.  The starting value is 5, because at that height the
                graph starts at the vertical axis.
step 3. Now the amount the graph goes down per step of 1 for x:
                 If you go 3 steps to the right, then you go down 2 steps.  So:
                If you go 1 step     to the right, then you go down       of a step.
step 4.  The Formula becomes:  b = 5 -       x a

               
            
x
0
3
6
y
5
3
1
32
32

Slide 19 - Tekstslide

The + and - signs make a huge difference:

Slide 20 - Tekstslide

PRACTICE PRACTICE PRACTICE ...
Now it's time you make a FORMULA for a GRAPH yourself!

Slide 21 - Tekstslide

FOTOVRAAG- to be handed in, in the next slide!
- have you got your:
   1. Notebook   2. pencil   3. geo  4. eraser    before you?
- if not, get it right now!
- the task starts; 
   1. make it in your Notebook   2. take a pic   3. send it in in!

Slide 22 - Tekstslide

Use the Method from p.218 
again!
FOTOVRAAG
timer
2:00

Slide 23 - Tekstslide

28a - my work on Andrews' Formula:

Slide 24 - Open vraag

Solution:

Slide 25 - Tekstslide

Homework time.
You may skip 25 and 26
Make §6.4 now.   Don't forget to:
+  check your work with the Solutionsbook


Slide 26 - Tekstslide