# 2TH §5.4 Quadratic formulas

Today's program
Questions about the homework? §5.3 Exercises 18, 19, 20 and 22
No upload in Classroom? That means: not done your HW

Entry Ticket
New theory: Quadratic formulas
1 / 17
Slide 1: Tekstslide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 2

In deze les zitten 17 slides, met tekstslides.

Lesduur is: 50 min

## Onderdelen in deze les

Today's program
Questions about the homework? §5.3 Exercises 18, 19, 20 and 22
No upload in Classroom? That means: not done your HW

Entry Ticket
New theory: Quadratic formulas

timer
4:00
Entry Ticket

#### Slide 2 -Tekstslide

Learning goals
I know what un upward opening parabola is
I know what a downward opening parabola is
I know what a vertex is
I know what the axis of symmetry means

#### Slide 4 -Tekstslide

Quadratic formulas
is a quadratic formula (it has a variable squared)

If we want to plot the graph of this formula, we should first make a table. Take the horizontal axis from -3 to 7.
y=2x28x

#### Slide 5 -Tekstslide

Filling in a quadratic formula

#### Slide 6 -Tekstslide

Filling in a quadratic formula

#### Slide 7 -Tekstslide

Plotting the graph for a quadratic formula

This table shows us we should take:
- the horizontal axis from -3 to 7 (with steps of 1)
- the vertical axis from - 10 to 45 (with steps of 5)

#### Slide 8 -Tekstslide

Plotting the graph for a quadratic formula

#### Slide 9 -Tekstslide

Plotting the graph for a quadratic formula

Plot all points from the table

#### Slide 10 -Tekstslide

Plotting the graph for a quadratic formula

Plot all points from the table
Connect with a smooth curve

#### Slide 11 -Tekstslide

Upward or downward opening parabola
Graphs for a quadratic formula are
called parabolas
This parabola is an
upward opening parabola.

#### Slide 12 -Tekstslide

Upward or downward opening parabola
In the coordinate system on the
right, the green graphs are
upward opening parabolas
and the purple graphs are
downward opening parabolas.

#### Slide 13 -Tekstslide

Upward or downward opening parabola
You will find that you can tell from the formula if a parabola is upward or downward opening.

If the number in front of
is positive, it is upward opening
If the number in front of
is negative, it is downward opening.
x2
x2

#### Slide 14 -Tekstslide

Vertex
The lowest point in an
upward opening parabola,
or the highest point in a
downward opening parabola
is called the vertex.

#### Slide 15 -Tekstslide

Axis of symmetry
All parabolas have
reflection symmetry.
The vertical line through
the vertex is the axis of symmetry

All vertical lines have a formula
x = ....

#### Slide 16 -Tekstslide

HW Tuesday
Do §5.4 Exercises 24, 25, 26 and 29
Check your answers with the solutionsbook!