3Tvwo §8.2 (A) and §10.2 (B)

• Wiskunde
• Middelbare school
• vwo
• Leerjaar 3

Welcome ...

+ to this first Long distance Lesson

+ Thanks to the technical developements you can work on ...

+ by yourself, but also a bit together,

+ starting right now with this LessonUp!

A: §8.2 Grouping data

B: §10.2 Altitude

An introduction for B follows now!

(Math A pupils, please follow this too.

It only takes a few slides and then I've got an introduction to your paragraph!)

So the subject for today is: the ALTITUDE (=hoogtelijn).

Of course the Challenge path is your learning path!

Comment:

As you can see in the previous picture:

+ an altitude (=hoogtelijn) is used to measure the distance from a vertex to the opposite side

+ an altitude can be outside the triangle!     

As you see in the Solution of 12a, you need:

+ a pencil

+ a geo triangle (straight lines, angle of 40 degrees)

+ a pair of compasses

+ forgetting these things is impossible now, because you are at home!!

Here you see the Solution of 14c.

Question: What Rules for Angles of Triangles are used here?

Answer this in the next slide!

These rules for triangles are:

1. opposite angles are equal
2. the angles of a triangle are 180 degrees together
3. a straight angle is 180 degrees
4. a triangles always has an obtuse angle

Answer:

1st:  the 3 angles together are 180 degrees

2nd: a straight angle is 180 degrees

3rd: opposite angles are equal

Homework time.

Good luck, doing §8.2!

(In Classroom or Study square.)

Math A, §8.2 Grouping data

A few fine points!

+ first a bit of Theory, then

+ 2 questions 

Study this closely; you can also use book 3B, p.15.

There is something tricky about 'intervals'! 

That's why we go on a bit on it.

Question:

What are the midpoints of these classes?

Fill in in next slide!

The midpoints of the classes are:

1. 3 8 13 mm
2. 2 8 12 mm
3. 2 7 12 mm
4. 2.5 7.5 12.5 mm

Answer: 2.5   7.5   12.5 

Why?

The first class goes from 0 to 5 (5 not included),

so in fact from 0 to 4.999999......

Now it is clear that 2.5 is in the middle.

Answer this question on the next slide!

(You might be surprised.)

Number of tickets is ...

1. 42
2. 42.5
3. 43
4. 43.5

Homework time

+  Good luck doing §8.2!

+  When you are stuck and the Solutionsbook is not clear enough for you,

+  you may mail me and I will provide you with an explanation.

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