# 1819 C2X §6.4

Which exercises should we discuss on the board?
1 / 13
Slide 1: Woordweb
WiskundeMiddelbare schoolhavo, vwoLeerjaar 2

In deze les zitten 13 slides, met interactieve quiz en tekstslides. Lesduur is: 50 min

## Onderdelen in deze les

Which exercises should we discuss on the board?

#### Slide 1 -Woordweb

Pythagoras in solids
This box has the shape of a cuboid.
We will call the cuboid ABCD.EFGH
The box is 6 by 12 by 6 cm.
We can use Pythagoras' Theorem to
find the lengths of line segments
inside the box, for example, the length
of line segment BH.

#### Slide 2 -Tekstslide

Pythagoras in solids
If we want to know the length of BH,
we should find a right-angled triangle
that has BH as one of the sides.
Cross section BDHF is a rectangle
with both vertex B and vertex H, so it
contains BH. And as we know, a rectangle makes
two right-angled triangles.

#### Slide 3 -Tekstslide

Pythagoras in solids
The box is 6 by 12 by 6 cm.
So we only know that HD = BF = 6 cm
We need to find the length of BD,
so we can calculate BH.

#### Slide 4 -Tekstslide

Pythagoras in solids
The box is 6 by 12 by 6 cm.
BD lies in the base of the box,so if
we sketch ABCD, we can calculate BD

#### Slide 5 -Tekstslide

Pythagoras in solids
The box is 6 by 12 by 6 cm.
BD lies in the base of the box,so if
we sketch ABCD, we can calculate BD

#### Slide 6 -Tekstslide

Pythagoras in solids
If we add the length of BD to our
previous sketch, we can calculate BH

#### Slide 7 -Tekstslide

Pythagoras in solids
If we add the length of BD to our
previous sketch, we can calculate BH

#### Slide 8 -Tekstslide

Pythagoras in solids
When using Pythagoras' theorem in solids, sketch the cross section that contains the line segment you want to know.
Often you will have to use Pythagoras' theorem in one of the faces of the solid first.

#### Slide 9 -Tekstslide

Pyramids
Cross sections in a pyramid are usually
isosceles triangles.

#### Slide 10 -Tekstslide

Pyramids
Cross sections in a pyramid are usually
isosceles triangles.

#### Slide 11 -Tekstslide

Pyramids
AS is half of AC, so

(and that is NOT          !!!)
SC=21200
100

#### Slide 12 -Tekstslide

HW Tuesday
Make and correct §6.4