+  §12.4 Linear formulas was about  STRAIGHT LINES.

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Slide 1: Slide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 1

This lesson contains 24 slides, with interactive quizzes and text slides.

Lesson duration is: 45 min

## Items in this lesson

+  §12.4 Linear formulas was about  STRAIGHT LINES.

#### Slide 1 -Slide

Graphs, graphs, graphs ...
As some graphs will be drawn by you in this paragraph,
now take before you:
+ a pencil, eraser and geo
In other words: The Right Stuff.

timer
0:20

A
abcd
B
abc
C
abd
D
c

#### Slide 5 -Quiz

Solution:
As you've just learned, in order to be a Quadratic Formula,
there must be a SQUARE of a VARIABLE in it!
So this rings true for: a, b and d.
Formula c contains a square all right, but not the square of a variable!

#### Slide 6 -Slide

Have you got a clue...
what the GRAPH for the FORMULA             =
looks like?
Next 2 slides show you all about it.
And more!
x2
y

#### Slide 7 -Slide

graph for:          =

This is the 'Mother' of all
y
x2

#### Slide 8 -Slide

Some points of attention for
the graph of:            =
+ watch the nicely rounded shape
+ it's name is: a PARABOLA
+ some 'easy to find' points in the
table are: (3, 9), (1, 1) but also:
(-3,9) and (-1,1)
y
x2

#### Slide 9 -Slide

This GRAPH for the formula:
y =            is ....
In this paragraph you will
are all variations of this one.
Next slide shows you a graph that is derived from (=afgeleid van) the
Basic graph.
x2

#### Slide 11 -Slide

What is the main difference
between this graph and the one
for                                           ?
Teacher gives a few turns to several pupils.
y=x2

#### Slide 13 -Slide

give you the neccessary practice for doing the
Homework.

#### Slide 14 -Slide

Calculate when x = -6

y=x2
timer
0:20
A
-36
B
12
C
-12
D
36

#### Slide 15 -Quiz

Solution:
y =
when we fill in:  x = -6,  we need BRACKETS:
y =             = -6 x -6 = 36   (and not -36!)
Let's practice a bit more with this, as it will make doing
x2
(6)2

#### Slide 16 -Slide

Now when x = -4,
calculate
Remember and key in, in the next slide!
y=x23
y

Calculate , when

y=x23
x=4
timer
0:30
A
-13
B
-7
C
-11
D
13

#### Slide 18 -Quiz

SOLUTION:               y =      -3
Now when x = -4,  we replace the variable      by  -4, as follows:
y =            - 3  =            -3  =  -4  x  -4  -3 = 16 - 3 = 13
x2
x
x2
(4)2

#### Slide 19 -Slide

about §12.5 follows in this Lesson Up.

Havo and H/V,  Do: S37, 37, 38, S39 and 39
VWO,                     Do: 38, 39, 40, C9 and C10
NOTE:     Study the Theory parts when they come up!

#### Slide 20 -Slide

Finally ...
You'll learn how to CHECK if a certain point lies on a graph.
We will study the Method HOW to check this.
If this isn't clear to you, then
study the Method on p.188, when doing the Homework.

#### Slide 21 -Slide

Suppose you have a graph and a point ...
and you want to know IF that point lies on the graph.
What to do to know for sure?
Let's study the Theory in the next slide together.

Homework time