This lesson contains 13 slides, with interactive quizzes and text slides.

Lesson duration is: 50 min

Items in this lesson

Gradient and y-intercept

2TTO

Slide 1 - Slide

Refresh assignment

See work sheet

- Answer questions (8 min)

- Check (2 min)

Slide 2 - Slide

Don't forget...

Draw with pencil + ruler

(table + graph) Axes max 10 cm long

Choose appropriate scale

(fixed step size!)

Mention variables along axes

Slide 3 - Slide

Linear relations

If there is a linear relation between two variables, you can make a linear formula. All linear formulas have the form

is the variable on the vertical axis

is the variable on the horizontal axis

is the gradient

is the y-intercept

y=ax+b

y

x

a

b

Slide 4 - Slide

What is the GRADIENT in the formula y = 3x - 4?

A

y

B

3

C

x

D

-4

Slide 5 - Quiz

What is the Y-INTERCEPT in the formula b = 2t + 8?

A

b

B

2

C

t

D

8

Slide 6 - Quiz

What is the GRADIENT in the formula t = 25 - 1.5h

A

25

B

-25

C

1.5

D

-1.5

Slide 7 - Quiz

Linear relation in a table

If there is a linear relation between two variables, you can see this in a table. In that case there is a fixed increase in the top AND bottom row of the table.

Slide 8 - Slide

Gradient in a table

Gradient = the fixed increase per step of 1 for the horizontal variable (variable in top row). So gradient =

steps of 1 in top row steps of 2 in top row

gradient = gradient =

Slide 9 - Slide

Y-intercept in a table

The y-intercept is the value in the bottom row when the value in the top row is 0. It is the value where the graph intersects the vertical axis

under 0 is 8 0 is not in the top row, 1 - 1 = 0 and 7 - 2.5 = 4.5

y-intercept = 8 y-intercept = 4.5

Slide 10 - Slide

Get to work

Work on ex 4 / 5 / 6 .

Work together, discuss questions + answers.

Check your work carefully, correct if needed.

Done? Ask teacher for challenges.

Slide 11 - Slide

Homework

(Monday 27 August)

Study answer model refresh assignment (if necessary)

Do ex 4/5/6/7 of par 1-1

Check and correct your work

Slide 12 - Slide

Exit question

Do these tables correspond to a linear relation?

Explain why or why not.

Give the formula for each table that corresponds to a linear relation.