1718 WB1Z CH1 (book 2A) Lesson 6

• Wiskunde
• Middelbare school
• vwo
• Leerjaar 1

Which exercises should we discuss on the board?

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

Parallel lines

Parallel lines have the

same gradient, because the

increase per step is the same.

(all graphs on the right go 3 units

up if you move 2 units to the right,

so the gradient is ...)

Parallel lines

Parallel lines have the

same gradient, because the

increase per step is the same.

(all graphs on the right go 3 units

up if you move 2 units to the right,

so the gradient is 1.5)

Making a formula (parallel lines)

A linear graph is parallel to the graph with formula                

AND it passes through point (3, 2). Give a formula for this graph.

y=−2x+5

Making a formula (parallel lines)

A linear graph is parallel to the graph with formula                

AND it passes through point (3, 2). Give a formula for this graph.

1) Write down the general linear formula

y=−2x+5

y=ax+b

Making a formula (parallel lines)

A linear graph is parallel to the graph with formula                

AND it passes through point (3, 2). Give a formula for this graph.

1) Write down the general linear formula

2) Fill in the gradient (parallel lines, so also -2)

y=−2x+5

y=ax+b

y=−2x+b

Making a formula (parallel lines)

A linear graph is parallel to the graph with formula                

AND it passes through point (3, 2). Give a formula for this graph.

1) Write down the general linear formula

2) Fill in the gradient (parallel lines, so also -2)

3) Fill in the coordinates from the given point  in the general formula and calculate b.

y=−2x+5

y=ax+b

y=−2x+b

Making a formula (parallel lines)

A linear graph is parallel to the graph with formula                

AND it passes through point (3, 2). Give a formula for this graph.

1) Write down the general linear formula

2) Fill in the gradient (parallel lines, so also -2)

3) Fill in the coordinates from the given point in the general formula and calculate b.

4) Give the formula

y=−2x+5

y=ax+b

y=−2x+b

y=−2x+8

A linear graph is parallel to the graph with formula
y =6x-7 AND passes through point (2, 1).
Give a formula that corresponds to this graph.

Making a formula (two given points)

You can also make a formula for a linear graph if you are given two points on that graph. The steps are almost the same as with making a formula for a graph and for parallel lines.

Making a formula (two given points)

A linear graph passes through the points (-4,3) and (2, 7). Give a formula that corresponds to this graph.

1) Write down the general linear formula.

y=ax+b

Making a formula (two given points)

A linear graph passes through the points (-4,3) and (2, 7). Give a formula that corresponds to this graph.

1) Write down the general linear formula

2) Sketch the points and calculate the gradient.

y=ax+b

Making a formula (two given points)

A linear graph passes through the points (-4,3) and (2, 7). Give a formula that corresponds to this graph.

1) Write down the general linear formula

2) Sketch the points and calculate the gradient.

3) Fill in the gradient and the coordinates of one of

the points in the general formula and calculate b.

y=ax+b

Making a formula (two given points)

A linear graph passes through the points (-4,3) and (2, 7). Give a formula that corresponds to this graph.

1) Write down the general linear formula

2) Sketch the points and calculate the gradient.

3) Fill in the gradient and the coordinates of one of

the points in the general formula and calculate b.

4) Give the formula

y=ax+b

y=​3​​2​​x+5​3​​2​​

HW Monday

Make and correct

33-40

from §1.5