2TTO 1-1 Gradient and y-intercept

• Wiskunde
• Middelbare school
• vwo
• Leerjaar 1

Gradient and y-intercept

2TTO

Refresh assignment

See work sheet

- Answer questions (8 min)

- Check (2 min)

Don't forget...

Draw with pencil + ruler 

(table + graph)
Axes max 10 cm long

Choose appropriate scale 

(fixed step size!)

Mention variables along axes

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

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

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

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

1. b
2. 2
3. t
4. 8

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

1. 25
2. -25
3. 1.5
4. -1.5

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.

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 =                     

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

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.

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

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.