### Blog Post for February 26, 2010

Sunday, February 28, 2010

Today in Math we watched a video about Scale factor, Similarity, and Proportions. Here is the link for the video: Scale factor, Similarity, and Proportions are related concepts2

# Now I will try to explain what I learned from the video, because its kinda hard to understand. As said in the video: Similar Figures have corresponding angles that are congruent and their corresponding sides are proportional. Corresponding means that the angles are matching and congruent means equal.

This polygons are equal, but how do you know if it is equal. First you need to get the scale factor of the polygons.

The first one is dividing the scale factors from the sides of the two polygons. If the answer is the same it means that the sides are equal.

The second way is multiplying the scale factors. You can multiply the scale factors any way you want, the answer would always be the same.

My post today is short, but I will try to update whenever I can. The next scribe is MARK ABAYA.

### Blog post for February,22,2010

Monday, February 22, 2010

Today in mathematics we got our stash its and journals back which was quite the horror and also our term marks which wasnt very pleasant either. But after the horrid stuff we got down to business with triangles and what not. This is what we've talked about this class:

Triangles vocabulary:
1.Scalene triangle - A triangle with no two sides of equal length.

This is a scalene triangle

3.Isosceles triangle - A triangle with two equal sides.

This is a Isosceles triangle

4.Equilateral triangle - A triangle has three sides, each one the same length. The three angles are also of equal measure.

This is an equilateral triangle

5.Acute triangle - A triangle whose interior angles are all acute (less than 90 degrees)

This is an Acute triangle

6.Obtuse triangle - A triangle that contains an obtuse interior angle.

This is an Obtuse triangle.

7.Equiangular triangle - A triangle in which each interior angle is identical, and each one will measure 60 degrees.

This is an Equiangular triangle.

8.Right-angle triangle - A right-angle triangle or a R.A.T. is a triangle with one right angle.

This is a Right-angle Triangle or a R.A.T.

Those are all the Vocabulary words from friday that we've talked about today. then after all that we then went to work on reviewing our triangle work last friday such as the formulas and how to figure out a side of a triangle and many more.

These are the examples from today:

So those are the three examples for today that we talked about and worked on. So now this is the homework:
1.Extra practice sheet 4.3
2.Workbook 4.3
3.Stuff from friday:
*Workbook 4.2
(all due tomorrow)

OH and also the next scribe is ...... ...... ...... ..... ...... ..... ..... Jethro Toledo
By the way dont forget to comment!!

### Scribe Post For February 19th.

Friday, February 19, 2010

Hey guys. (:
Alright, well. Today in math we corrected our math test.. Here are some corrections :

MULTIPLE CHOICE
Question #1 - Answer is B
Question #2 - Answer is C
Question #3 - Answer is A

Question #4 - Answer is B
Question #5 - Answer is D
Question #6 - Answer is C
Question #7 - Answer is D

MATCHING
Question #8 - Answer is B
Question #9 - Answer is E
Question #10 - Answer is A
Question #11 - Answer is D

Question #12 - Answer is ..
60/8 = 0.17
100cm x 0.25 = 25cm.
Jason used 0.25 as a scale factor.

Question #14 - Answer is ..
1.6/100= 3.2/x 1.6x=320
x=200cm x=200

x=2m
Question #15 - Answer is ..
L-2, 24
W-1, 12
12x3.5=42cm
24x3.5=84cm
12x0.75=9cm
24x0.75=18cm

That's all for the test corrections, after we finished correcting the test we learned some stuff about triangles. There are 7 types of triangles:
Scalene Triangle
Isosceles Triangle
Equilateral Triangle
Acute Triangle
Obtuse Triangle
Equiangular Triangle
Right-Angle Triangle

Similar Triangle/Polygons = Have the same SHAPE but DIFFERENT SIZE. They have EQUAL CORRESPONDING angles.

Okay, well. That's all! The pictures I put above were just some notes that we took. I'm sorry if I made any mistakes at all. The next scribe that I pick is ... RENZ A. Sorry, Renz. :P Oh, and leave comments.

### Scribe Post for February 17 2010.

Wednesday, February 17, 2010

Okay. I don't really know who is the scribe for today so i'm just going to do it myself. Mr.B is the scribe posts for marks?? :)

Okay. anywho in class today we talked about ENLARGMENT and REDUCTION.

So can anyone guess what Enlargment? . never mind. you can't answer that.

Anywho! Enlargment is to make something bigger, propotionally, everything has to be enlarged by the same scale factor. Enlargement always has a scale factor of >1

For example:

In order to do that we have to find what the scale factor is.
The scale factor is 1.5.

2 x 1.5 = ....

Hmm lets think. oh wait it equals to 3

So the scale factor would be 1.5 and this is a diagram to show that.

Example 2 :

and that's what Enlargement do.

Now to the next one.

REDUCTION

Reduction is to make a scale smaller, proportionally everything has to be reduced by the same scale factor. A reduction always has a factor between o and <1.

Sorry i don't have any example for this one. :(

Anywho.! Mr. B also said that we have a test tommorow and its on 4.1 and 4.2 and we also need to know what scale and scale factor means.

Okay so this is it for today. I'll see you next time. Wait i can't really see but i'll do a scribe post next time.

Im too tired to pick the next scribe soo. umm.
Okay im just going to pick randomly Nichole Sr is the next scribe.

Nichole you better do this scribe post. i think its for marks

BTW
< - Less Than >-Greater than

### Scribe Post for February 8, 2010

Monday, February 8, 2010

Heeeello guys! (:
Okay so, today we began our math class by making corrections to our chapter 3 test. After that, Mr. Backé handed out worksheets to us about scales and scale factors, Mr. Backé also handed out worksheets for chapter 4. Mr. Backé told us to copy out the definition for scale and scale factor out of our textbook.

Scale: A comparison between the actual size of an object and the size of it's image. This can be expressed as a ratio, as a fraction, as a percent, in words, or in a diagram. For example, a scale of 1cm: 50km on a map means that 1cm on the map represents 50km.

Scale Factor: The constant factor by which all dimensions of an object are enlarged or reduced in a scale drawing.

*REMINDER:
On Tuesday, February 16 Mr. Backé will be collecting the following in a "stash it":
1) Math Link Introduction
2) Math Link 3.1
3) Math Link 3.3
4) Math Link 3.4
5) Math Link Wrap It Up
6) Chapter 3 Self Assessment
7) Tests Signed By Parents
8) Journal
* All pages should be completed for 20% of this units mark.

I pick Breann as the next scribe.
Sorry if this scribe is short, I tried. (: