1TH/vwo §11.4+§11.5 MORE PRACTICE!

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

But first...

Open your Notebook and take a

- pen, pencil, eraser 

- from your pencil case!

The coordinate system is something you have to KNOW.

Next is making a FORMULA for a STRAIGHT GRAPH.

This something you have to UNDERSTAND!

 

2 things are important to know,

when making a formula for this graph: 

1st:  at what height does the graph go through the vertical axis?

2nd:  how much does it rise when going one step to the right?

Next slides show you the Method and an example, completely worked out!

Now it's your turn! Step by step.

Task 1                                   

Step 1: Mention a GRID POINT in this graph in the next slide. Don't forget the brackets!

Answer in the next slide.

A grid point: (..., ...)

Grid points are:

(-1, 4) (0, 2) (1, 0) (2, -2)

So: no fractions, but whole numbers!

Task 2.  

STEP 2:     Read off the start number. 

Key in in the next slide.

The start number is:

1. 0
2. -2
3. 2
4. (0, 2)

The start number is ..... 2!

At the height of 2 the graph goes through the

vertical axis. That's why!

Task 3:          Step 3:

Work out in your head how much the graph rises or falls per horizontal step of 1.

Key in in the next slide the number 

that has to be filled in!

The number is .....

1. 2
2. -2
3. 1
4. 1/2

SOLUTION:                                 Task 3:          Step 3:

Work out in your head how much the graph rises or falls per horizontal step of 1.

Per step of 1 the graph falls by 2 steps.

So: the value of y decreases (=gets less)

by 2.

Task 4          Step 4:  Key in the right formula in the next slide.

The formula is:

1. y = -2x + 2
2. y = -2 + 2x
3. y = 2 - 2x
4. y = -2 - 2x

 SOLUTION:   Task 4          Step 4:  Key in the right formula in the next slide.

We now fill in the numbers 

from steps 2 and 3:

y = -2x + 2   or 

y = 2 - 2x     or

2 - 2x = y

High time for a recap on §12.5 now, but ...

even higher time for a JOKE!

The last thing you have to know is this:

suppose you've got a Parabola and a Point given.

How can we find out -by Calculating!-  IF the point lies on the graph?!

NOTE: we don't draw the graph, to check it. Too much work

for us, lazy bones!

Task 4:

FOTOVRAAG:  Work this out in your Notebook, take a picture and send it in!

My Calculation:

Solution Task 4:

Watch the next slide too!

Addition:  From the Graph you can see that it is necessary to Calculate it, because x = -5 is not visible on the graph!!

1T HV classes:

Homework time- Finish all the Homework for Ch11!

Here is an OVERVIEW of all the tasks to make:

§11.1. t/m. §11.5 as follows:

§11.1    Skip  1, 5 and 7

§11.2   Skip 8 and 10

§11.3   Skip 15 and 16

§11.4   Do  25, 29, 30, 31 S28 + S30

§11.5   Do the Support path