Diana's Algebra Post

Algebra: Writing mathematical phrases using letters to show numbers
Variable: The unknown, Use a letter to represent a number
Constant: The integer in an algebraic expression or equation
When there are (-) multiply and divide cancel with the same integer


Solving Step One Equations:
1) Isolate the variable
2) Cancel the constant using zero pair
3) Balance, doing it to both sides
4) Verify to check


Solving Step Two Equations:
1. Isolate the variable
2. Cancel the constant
3. Balance
4. Simplify the variable
5. Balance
6. Verify



I found this "website" very helpful, maybe it will help you understand algebra more too.

Diana's Great Big Book of Integers

Chapter 1
Grade 7 Integer Review:


(+4)-(-4) =0
Positive 4 subtract Negative 4 = 0
You have 4 and you owe 4 = 0 or none

(+6) + (-2) = +4
Positive 6 and Negative 2 = Positive 4
You have 6 and you owe 2 = have 4

Zero Pairs:

-6=+6

-20=+20

-10=+10

-5=+5

-1=+1

-4=+4

-50=+50

Chapter 2
Multiplying Integers:

SIGN RULE:
Odd: When you have a odd number of negative the product is negative.
Even: When you have a even number of negative factors the product is positive.




(+2)x(-3)=
2 groups of (-3)=(-6)

(+2)x(+3)=
2 groups of (+3)=(+6)



(-2)x(+3)
2 groups of (+3)=-6

(-2)x(-3)
2 groups of (-3)=6

Chapter 3
Dividing integers:
SIGN RULE:
If you have no negative or an even number of negative signs in a division question, the quotient is postive.

There are 2 types of division:
Partitive division:
Partitive division is making parts.
Example:
6 divided by 2= 3

6 divided by -2= -3


Quotative division:
Quotative division is sharing your total, with groups.
Example:
(-6) divided by 2= -3

6 divided by (-2)= +3

Chapter 4

Use Badmas:
B ...stands for brackets
E ...stands for exponents
D ...stands for division
M ...stands for multiplication
A ...stands for addition
S ...stands for subtraction
(Use in order)

If I had to solve this problem:
(+5) x (-3) + (-6) ÷ (+3)=
First I would put brackets around, (-6)÷(+3). Then solve it.
[(-6)÷(+3)]=(-2)
Now the question would be:
(+5) x (-3) + (-2)=
Multiplication is next:
(+5) x (-3)= (-15)
Now Answer:
(-15) + (-2)= (-17)

Term 2 Reflection.

Hello, My name is Diana Rodrigues and I’m a grade 8 student. This term in math we did converting fractions, percentages, volumes, and surface areas. I did well on finding the surface area of different shapes. I found this chapters one of the easiest ones that we did so far. Also I did well on drawing nest and making 3D shapes on graph paper. The tests for Prisms and Cylinders weren’t even hard, I’d only get a couple wrong. Also I did pretty good on finding the volume of all those shapes. I really got how to do it, It easy to understand.

I wasn’t very good at remembering all the formulas for all the different shapes. Also I wasn’t very good with finding percentages and converting fractions. I often got confused. I kind of struggled on finding the volume of a shape inside of a shape, but after a while of doing it I kind of get it now.

For term 3 I’m going to try to get better in math by, doing more blogs, asking questions and finishing my homework. I want to be ready for grade 9 because I don’t want to fail. Try to finish all the questions that Mr.Harbeck assigns me, because they will help me understand it more and it will be easier for me on tests. I will also try not to rush on test, so I`ll read everything it is asking me to do. Also, I would like to do better on my blogs by doing more then Mr.Harbeck asked me to do, and try to comment on everyithng that is published. So that’s how I would want to get better.

I will post my Audioboo when I get it to work on my computer.

Diana's Homework Book Post.

Even numbers, Pages 78-79.

4. A)

B)

C)

6. A)

Both rectangular prisms have the volume of 200cm.

B)

Both rectangular prisms have the volume of 10.5 m3.

8.

The need to put 24.3m3 of water in the pool.

Here are some Videos to help you guys! (:

Comment if I did anything wrong.
Also , sorry that a couple of my pictures are not the right way they wouldn't want to rotate.



Chapter 7.3

Jumbo:
r= d÷2 V=(pi.r.r)x h
r= 20÷2 V=(3.14x10x10)x40
r=10cm V=314 x 40
V=12'560cm³


Popcorn Lover's:
r= d÷2 V=(pi.r.r)x h
r= 30÷2 V=(3.14x15x15)x20
r= 15cm V= 7065 x 20
V= 14'130cm³

Martha should buy the popcorn lover's one because it has a greater volume than the Jumbo one.Popcorn Lover's volume is 14,130cm³ and Jumbo's 12,560cm³.



Chapter 7.4





Outside;
r=d÷2 V=(pi.r.r)x h
r= 1÷2 V=(3.14x0.5x0.5)x10
r=0.5m V= 0.785 x 10
V= 7.85m³


Inside;
r= d÷2 V=(pi.r.r)x h
r= 0.8÷ 2 V=(3.14x0.4x0.4)x10
r= 0.4m V=0.5024 x 10
V= 5.024m³


You Subtract the volume of the inside from the volume of the outside.
7.85m³ - 5.024m³ = 2.826m³


The volume of concrete needed to make the culvert is 2.826m³

Diana's Percent Scribe post.

3.


A) 300%= 3.3x 2000 = 6000


B)1 + 1/4% = 0.0125


0.0125x60=0.75

C) 0.1% = 0.001

0.001 x 40 = 0.04





4.

A) 20% = 0.2

0.2 x 60 =12

B) 250% =2.5

2.5 x 400 = 1000

C) 10 = 1/2% = 0.105

0.105 x 100 = 10.5





8.


The original price of a jacket was $84.00. A store manager marked the price down by 25.5%. By how much the price reduced ?



The price was reduced by $21.42.

comment if I got anything wrong :)

Diana's Pay it Forward

Part 1:
The idea of pay it forward was inspired by a boy named Trevor who was assigned an assignment from his social studies teacher to think of a way to change the world. He thought of the idea of helping three people and those three people help three more people, kind of like a chain reaction. it never stops as long as you pay the act of kindness forward. The more people you pay it forward to, the more people they it forward to and so on.

Part 2:
Tonie, Casey, and I decided to pay it forward and go door to door asking for donations to help us raise money to give to Christmas Cheerboard. Also, when someone gave us money, we gave them candycanes and a Christmas card that says; " Happy Holidays, your donation is greatly appreciated! Love, Sargent Park Students." Because we wanted to thank the people who he;ped us raise money. My group did this act of kindness on December 16th, 17th, and 19th 2010.

Part 3:
After we raised some money we went to the Christmas Cheerboard. When we told the Christmas Cheerboard. When we told the front desk that we had money for them they seemed shocked that three young girl would do that. When they brought us to Linda the lady that works the donation office, she was so happy that we would even think about doing this. She showed us around and how everything works. Just the way she made us feel when we gave her the money is unwriteable. Also we are going back after Christmas to help roll pennies.We also went superstore, Rona and wal-mart to raise money but sadly they wouldn't let us. Although it was really cold to go door to door it still felt good that we were going to help people.

Part 4:
This idea of paying it forward is important because just one person can make a difference!

Don't forget to pay it forward! :)

Diana's Pythagoras Scribe Post

Homework for the weekend : Pages 91-94 #1-21

My homework was questions : 3, 8, 11, & 16




3. Kendra wrote the Phythagorean relationship as r2= p2 + q2. Is she correct ? Explain.


Kendra is incorrect. Leg2 + leg2 = hypotenuse2. Since the legs are r and q and the hypotenuse is p, It should be r2+q2=p2 or q2+r2=p2.




8. Is the triangle shown a right triangle ? Explain your answer.


The triangle is not a right triangle. For this triangle to be a right triangle, the area of the two smaller squares must equal the area of the larger one. Because a + b = 60 not 50.




11. The side lengths of a triangle are 5 cm, 6cm, and 8cm. Determine whether the triangle is a right triangle. explain.

It is not a right triangle since the sum of the areas of the two smaller squares aren't equal to the larger square. (6x6)= 36cm2 , (5x5)= 25cm2, 36+25=61. 61 doesn't equal 64.




16. Baldeep is building a wooden box for storing coloured pencils. The box will have rectangular sides that are 12 cm wide and 20 cm long. Show how Baldeep can be sure the sides are rectangular, without using a protractor.

A2 + B2 = C2 ,
(12x12)+(20x20)= C2,
144cm2 +400cm2= C2,
544cm2= C2.
The box with be 544cm2.


Video:



Tell me if I did anything wrong. Also make sure to have all your work done for monday.

Diana's Math Profle.

Hi, my name is Diana. I'm a math student in grade 8. If someone asked me if I liked math I would say not really. Its not a subject I like doing. I'm not good at it but I like solving some of the problems even if I'm wrong. I remember in grade 6 when we would play a lot of math games & problem solving. I liked doing problems solving with real life problems. Math in grade 6 was way easier to me.


In Grade 7 I really liked learning about mean, median, mode, outlier, and range. The way Mr. Isfeld taught us, I could really remember. I also remember not being good at integers because I was gone while Mr. Isfeld taught the class, and I didn't ask the teacher & students for help.


This is now grade 8. I know that by finishing my homework, I will help me get a better grade in math. I also want to learn more about square numbers and square roots because I find it to be easy. I'm looking forward to doing Algebra in grade 9.


I was a blogger last year. http://room42math09.blogspot.com/2010/06/five-top-for-tests.html this post is about answering test questions also for exams. I like this post because it was really colorful and this was one of the best posts I've done. On this post I got 18 comments, it's not really though. This year, I hope I do a lot more posts and get a lot of comments.

Diana's Sesame Street Video Post.

Part One:
Two-term ratio; Compares 2 quantitesmeasured in the same units. (a:b)
Three- term ratio; Compares 3 quanites measured in the same units. (a:b:c)
Part to part ratio; Compares different parts of a group to each other. (b:c, 6:5)
Part to whole ratio; Compares to parts to the whole group. (b: all letters, b:21)

Rate; Compares 2 quantites measured in different units. (2km/1hr)
Unit Rate; A rate where the second rate is one. ($15/1hr)
Price Rate; A rate used when shopping. ($2/1mL)

Proportion Reasoning; A relationship that says that two ratios or two rates are equal. (2/3 = 6/9. (x3) )


Part Two.
The Original Video.


This Video is about Abby Making a doll for elmo.

Part Three.
Our remake of "A doll for Elmo"
"A Ratio for Elmo"



Our remake video was composing the definitions of Ratios, Rates, and Proportions.