# 4-1 Linear formulas

Linear formulas
(p. 104)
What you need:
- Textbook, writingbook, iPad
- Pen, pencil, geotriangle
- Calculator

Schoolbags in the cuboard
Phones in the phonebag
Bluetooth
- ON
- VPN off
1 / 20
Slide 1: Slide
WiskundeMiddelbare schoolhavoLeerjaar 3

This lesson contains 20 slides, with interactive quizzes and text slides.

Lesson duration is: 50 min

## Items in this lesson

Linear formulas
(p. 104)
What you need:
- Textbook, writingbook, iPad
- Pen, pencil, geotriangle
- Calculator

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

#### Slide 1 -Slide

Lesson goal
Identify linear formulas

Use the standard form for a linear relation y=ax+b

#### Slide 2 -Slide

Linear relation
If the numbers in the top row are consecutive whole numbers, and there is a fixed increase per step in the bottom row, then there is a linear relation between the variables.

#### Slide 3 -Slide

Is this a linear relation?
A
Yes
B
No

#### Slide 4 -Quiz

Is this a linear relation?
A
Yes
B
No

#### Slide 5 -Quiz

Which of these are linear relations?
A
1
B
2
C
2 and 3
D
All of them

#### Slide 6 -Quiz

The formula for a linear function

y=ax+b

a is the gradient
b is the y intercept

#### Slide 10 -Slide

If the gradient is positive,
the graph is increasing (uphill)

If the gradient is negative, the
graph is decreasing (downhill)

If the gradient is 0, it is a horizontal line.

#### Slide 11 -Slide

Parallel lines - same gradient
If two lines are parallel, they have the same gradient