# 8-1 Solving by factorising

8-1 Solving by factorising

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Slide 1: Tekstslide
WiskundeMiddelbare schoolhavoLeerjaar 3

In deze les zitten 35 slides, met interactieve quizzen en tekstslides.

Lesduur is: 50 min

## Onderdelen in deze les

8-1 Solving by factorising

What you need: - Textbook, writingbook, iPad - Pen, pencil, geotriangle - Calculator

Schoolbags in the cuboard
Phones in the phonebag
Bluetooth
- ON
- VPN off

#### Slide 1 -Tekstslide

Lesson goals
• Solve equations with factorisation.
• Factorize a difference of two squares.

#### Slide 2 -Tekstslide

A x B = 0
In this case A = 0 or B = 0

A quadratic equation is not written in the form A x B = 0 can be solved by factorising.

#### Slide 3 -Tekstslide

Solve the following equations:
timer
10:00

a
A
x=0 or x=-4
B
x=0 or x=4
C
x=0 or x=-2
D
x=0 or x=2

b
A
x=0 or x=-3
B
x=0 or x=3
C
x=0 or x=-1/3
D
x=0 or x=1/3

c
A
x=0 or x=-2,5
B
x=0 or x=2,5
C
x=0 or x=-5
D
x=0 or x=5

d
A
x=3 or x=6
B
x=3 or x=-6
C
x=-3 or x=-6
D
x=-3 or x=6

e
A
x=7 or x=2
B
x=-7 or x=2
C
x=7 or x=-2
D
x=-7 or x=-2

f
A
x=3 or x=5
B
x=-3 or x=5
C
x=3 or x=-5
D
x=-3 or x=-5

timer
5:00

5a
A
y=x221
B
y=x210x21
C
y=x2+10x21
D
y=x2+4x21

5b
A
y=x29
B
y=x2+9
C
y=x26x+9
D
y=x23x+9

5d
A
y=x225
B
y=x2+25
C
y=x250x25
D
y=x2+50x+25

5e
A
y=x2+4
B
y=x24
C
y=x28x4
D
y=x2+8x+4

#### Slide 17 -Tekstslide

Factorizing a difference of squares
x281=0
(x9)(x+9)=0
x9=0
x+9=0
or
x=9
x=9

8a
A
x=-10
B
x=0 or x=10
C
x=0 or x=-10
D
x=10 or x=-10

8b
A
x=0 or x=-9
B
x=9 or x=9
C
x=9 or x=-9
D
x=9

8c
A
x=0 or x=-1
B
x=-1
C
x=1
D
x=1 or x=-1

8d
A
x=4 or x = -4
B
x=0 or x = -4
C
x=4
D
x = -4

#### Slide 24 -Tekstslide

1, 2, 5 and 7
RULES:
• Use: Textbook
• Discussion when you are stuck is allowed

Extra excercise: 4
Challenge: 6, 7
Homework: 3, 7, 9 (p. 38)

#### Slide 29 -Tekstslide

If you forgot what cards are, look on page 37 of the textbook.