Sunday, December 18, 2011

Shane's Blog Post

Question 22

SAS= Side Angle Side rule
ASA= Angle Side Angle rule
SSA= Side Side Angle rule

HW:
Practise 3,5,6
Apply- all
Extend- any 3 of 13,14,15,16 and 17
*MANGAHIGH*

Wednesday, December 14, 2011

Cathlene's Blog Post

4.3 Similar Triangles

Proportional - in a shape it means same shape but different size

Corresponding - a comparison of two similar sides or angles in an object

Corresponding: LA ~ LD
LB ~ LE
LC ~ LF

LA = LBAC = LCAB LD = LEDF = LFDE
LB = LABC = LCBA LE = LDEF = LFED
LC = LACB = LBCA LF = LEFD = LDFE

Corresponding angles will ALWAYS be equal

The vertices are always upper case
Sides are always lower case

Example 2 ( Question 2 )

Homework
Check Your Understanding #1 and #2
Practise odds or even
Apply all question
Extend #18, #20, #22, #23

Tuesday, December 13, 2011

4.2 Scale

SCALE: is a comparison of two objects; the actual size and its diagram.

Scale can be expressed as a ratio, as a fraction, as a percent, in words or as a diagram.A scale of 1:50 means that 1 unit on the diagram is equal to 50 units of the actual object.

Scale Diagram: is similar o

r t

he actual or object. It main

There

are two ways to find a missing length of proportiontain proportion, the diagram may be longer or smaller than the actual object.

Example One: Use scale to determine the Actual Length of an Object.

For a scale of 1:14 and a

diagram measuring 5.5c

m set the proportion.

SCALE: is a comparison

of two objects; the actual size and its diagram.

Scale can be expressed as a ratio, as a fraction, as a percent, in words or as a diagram.

A scale of 1:50 means that 1 unit on the diagram is equal to 50 units of the actual object.

SCALE DIAGRAM :Is similar or the actual or

object. It maintain proportion, the diagram may

be longer or smaller than the actual object.

There are two ways to find a missing length of proportion

For a scale of 1:14 and a diagram measuring 5.5cm set the proportion.Example One: Use scale to determine the Actual Length of an Object.

Because it is easy to find the relationship of 1 to 5.5 it easy to find x, simply multiply 14 by 5.5 to find x=77cm- So the act
ual object is 77cm.

x= 5.5(14) x=77cm

Becau

se it is easy to find the relationship of 1 to 5.5 it easy to find x, simply multiply 14 by 5.5 to find x=77cm- So the actual object is 77cm.

Example Two: Use Measurement to find Scale.

So the scale is 1:2400000cm or 1:24km

Dont forget to do all the textbook work, worksheets and workbook work!!
And all mangahigh challenges are for marks! Keep playing! (:

Monday, December 12, 2011

Jocelyn's blog post on todays lesson

Today we learned about Enlargements and reductions.
Enlargement is to make something bigger. In mathematics we need to multiply by a factor greater than 1 to make it an enlargement. (eg. 3x2)
Reduction is to make something smaller. In mathematics we need to multiply by a factor that
is less than 1 but greater than 0 (eg. 7x0.2)
Scale Factor- the constant factor by which all dimensions of an object are to be inlarged or reduced. some examples of this is:
If a rectangle that is 3x5 is to be enlarged by a scale factor of 1.3 the new dimensions would be
3.9x6.5. If that same rectangle was to be Reduced by a scale factor of 0.6 the new dimensions would be 1.8x3
To make Enlargements and Reductions it must be proportional, maintaining its original shape, but not size.
Enlargements and Reductions can also be made on different sized graph paper. This method is often used by artistswhen drawing large murals from a small original, vice versa.
Homework:
Workbook 4.1
text 1,3
practise odd/even
apply 9,11,12,13
extend 14, 15, 17
extra practice worksheet

Saturday, December 3, 2011

Lizelles text book question.

I'm truly sorry that this is late!!
My text book question is 27 on 2.4

"The surface area of a cube is 100 cm squared. Determine the edge length of the cube, to the nearest tenth of a centimetre."

A CUBE has 6 faces.

Since I knew that, I divided 100 cm squared by 6 to give me one face.
That got me 16.66 cm squared.
Since I wanted to get rid of the squared, I did a square root of a 16.66.
For that, I got 4.082.
I rounded that to the nearest tenth, and I got 4.1.

I checked at the book, and I got the same answer.

My question:

My work:

Thursday, December 1, 2011

Jocelyn's textbook question 2.4

Question #19 in 2.4
A square picture with an area of 100cm^2 is mounted on matting 2.5 times the area of the picture. If the picture is centered on the matting, what is the width of the matting that is showing? Give your answer to the nearest tenth of a cm.
this is my work:
100x2.5=250
the square root of 100=10
the square root of 250=15.8113883
15.8113883-10=5.811388301
5.811388301/2=2.90569415
2.90569415=2.9
the width of the visible matting, to the nearest tenth of a cm. is, 2.9cm^2

Colleen's Blog Post

What we did in class today:

*You need to know the formula's for 3.4

Bacteria triples every 15 minutes.
The coefficient is 50.

50(3^1)
In one hour: 50(3^4)
In three hours: 50(3^12)
t hours: 50(3^4t)

Question from yesterday:

Homework:
3.4- Show You Know