Angel's Algebra Post

ONE STEP EQUATIONS

1. Isolate the variable
(Variable - The unknown number and you use a letter to represent the number.)

2. Cancel using the opposite
-create a zero pair for the constant
(Constant - The integer in an algebraic expression or equation.)
2x = 6 equation, 2x = expression

3. Balance on the other side of the equal sign

4. Verify your answer

Eg:
A number and 16 is 9.










The difference of a number and 15 is -27.









Eight times a number is -104.









A number divided by 18 is -6.

Diagrams for one step:

TWO STEP EQUATIONS

1. Isolate variable
2. Cancel the constant
3. Balance
4. Simplify the variable
5. Balance
6. Verify


Division:












Multiplication:

Diagram for two step:

Here's a link and two videos that might help you out more in algebra.

Again sorry my laptop won't let me embed the videos.

4. Adding proper fractions with different denominators

Embedding my video won't work, when I try to do it my internet keeps crashing but here's the link to it. Here's a video. Here's a site that might help you. Again, sorry it won't let me embed the video.

Angel's Great Big Book of Integers

Chapter 1 Grade 7 Integer Review

(+4) + (-4) = 0
have 4 owe 4
*Brackets are training wheels. Pure standard form: 4 - 4-

Zero pair = When subtracting something that isn't there, use a zero pair.
Examples of zero pairs: +6 -6, +10 -10, +19 -19, +16 -16, +11-11,+14 -14, +63 -63

-3 -2 = 3-2 = subtraction = adding a negative integer.

5. -3 - (-7) = +4








6. -3 - 7 = -10

7. 3 - 7 = -4

8. 3 + 7 = 10







9. -3 + 7 = -4

Chapter 2 Multiplying Integers

(+2) x (+3) = 6
(2)x(3) = 6
(2)(3) < style="font-weight: bold;">

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

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

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

The negative sign on the first integer is saying to remove 2 groups of (+3)

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

Sign Rule (negative signs)
Even = When you have an even number of negatives factors the product is POSITIVE.
Odd = When you have an odd number of negative factors the product is negative.

Homework: 290-292 1-19 odds

HWB: 8.1 90-91

Chapter 3 Dividing Integers

2 types of division:

6/3 = How many groups of (+3) are in 6?

Paratative division or making parts.

6/3=2 Share 6 with 2 groups

Quotative division or sharing your total with groups

(-6)/(-3)=2

How many groups of (-3) are in (-6)? 2 groups

*Only partative will work.

6/3=2
2x3=6

3x2=6

(-6)/(-3)=2

2x(-3)=-6

(-3)x(2)=-6

If you have no negative or an even number of negative signs in a division question the quotient is positive. When you have an odd number of (-) signs in a division question the quotient is negative.

HWB: 96 & 97

Chapter 4 Great Big Book of Integers

How I would solve this equation: (+5) x (-3) + (-6) / (+3)

First, I would follow the rules of BEDMAS, so I'd put square brackets around (-6) / (+3)

After, I would solve what (+5) x (-3)

Then I would add the two answers together which would equal to -17.

(+5) x (-3) + [(-6) / (+3)]

-15 + -2

= -17

Term 2 Reflection

Hello there, my name is Angel Malapit and I’m a grade 8 math student. Term 2 was a pretty good term for me, I found our chapters fun and not as complicated. We learned about converting fractions, percentages, volumes, and surface areas. I did well on nets and found it easy to draw 3D shapes on the graph paper. I enjoyed doing formulas, finding surface areas and volumes of cylinders, rectangular prisms, and triangular prisms because I found them easy to understand.The quizzes and tests weren’t difficult about shapes and their volumes, I would get 90-100%.

Although, I wasn’t very strong with finding percentages and converting fractions. I often got confused when we would be solving a problem or doing a test. I also struggled in finding the volume of a prism inside a prism, I would get confused when they would tell you to round the answer to the nearest centimetre when it gives you metres. But I got Mr. Harbeck to help me out on that.

For term 3, I will continue to do all my homework and finish my textbook pages Mr. Harbeck assigns me. Finishing those pages really helped me understand more and made it easier for me on tests because I got a lot of practice. I will also try not to be lazy to read everything on a test because sometimes I rush and would get my answers wrong. That was a mistake I learned from. Also, I would like to do better on my blogs by giving more than what’s expected and comment every time there is work published because i would usually procrastinate and then I’m left with a whole bunch of posts to comment on. So that’s how i would want to get better.

What i learned about findings surface areas and volumes is that following the formula is very important. Like for cylinders, the formula for finding the volume is first you have to find the radius from the given diameter and the formula for that is base x height / 2, then you multiply pi x r x r x h, that’s how you would find the volume of a cylinder. I learned how to reduce a price with a given percentage, how to find the total cost of an item including taxes, how to convert fractions and decimals, I’m not the best at that, I still get confused but that’s something I will have to practice. I also learned that the difference between volume and surface area, is that volume is a measurement of the space a 3D object takes up, while surface area is the area of a 2D object.


I'll add my audioboo when I get it to work on my computer!

HWB pg. 80 & 81 #4, 6, 8

4. Calculate the volume of each rectangular prism.
a) l = 15cm, w = 12cm, h = 3cm

v = l x w x h
15cm x 12cm = 180cm2
180cm2 x 3 = 540cm3

b)

v = l x w x h
8.5m x 7m = 59.5m2
59.5m2 x 2m = 119m3




c)

v = l x w x h
20cm x 8cm = 160cm2
160cm2 x 16cm = 2560cm3










6. Calculate the volume of each right triangular prism. Express the answer to the nearest tenth.

a)

v = b x h1/2 x h2
7.2 x 4.5cm/2 = 16.2cm2
16.2cm2 x 10cm = 162cm3








b)
v = b x h1/2 x h2
5 x 3/2 = 7.5cm2
7.5 x 8.5 = 63.8m3








c) A prism where the case of the triangle is 4m, the height of the triangle is 5m, and the prism height is 12m.

v = b x h1/2 x h2
4 x 5/2 = 10m2
10m2 x 12 = 120m3

8. Wab needs to buy drinks for the summer barbeque. Both containers are the same price. Which one holds more?

apple juice:
v = l x w x h
6cm x 9cm = 54cm2
54cm2 x 4.5cm = 243cm3

orange juice:
v = l x w x h
6cm x 10cm = 60cm2
60cm2 x 3.75 = 225cm3

Apple juice holds more juice (y)

Here is are links to help you out with finding out prism: 1, 2, and 3.

Here's a video:


URL of pictures:
http://www.clker.com/clipart-3934.html
http://www.ifood.tv/blog/apple-juice-health-benefits

Please tell me if I did any mistakes or what I can do better next time. (:



Cylinder Volume and Volume Problems

Chapter 7.3:

v = π r r h
v = (3.14x5cmx5xm) x 23
v = 1805.5cm3










Chapter 7.4:












Volume of cylinder: Volume of triangular prism:

r=d/2 bxh1/2 x h2
r=25/2 40x35/2 x 140cm2
r=12.5cm2 = 98000cm3

v=π r r h
v= (3.14x12.5x12.5)x100
v=49062.5cm3

98000cm3 - 49062.5cm3 = 48937.5cm3

Video:

* I meant to say cubed when I said squared on the part where i was supposed to say cubed :P

Angel's Final Percent Post

A percent means out of 100, also another name for hundredths and can be expressed as decimals or fractions.

Representing percents

Shade squares on a grid of 100 squares called a hundred grid to represent a percent. A completely shaded grid represents 100%. If you shade more than one grid, that represents a percent greater than 100%. To represent a fractional percent between 0% and 1%, you have to shade part of one square. Also, to represent a fractional percent greater than 1% you have to shade squares from the hundred grid to show the whole number, then shade part of a square from the grid to show the fraction.





















Fractions, Decimals, Percents

Percents can also be represented as a decimal or a fraction.
Eg. 80% = 0.8 = 4/5


Percent of a Number

You can use mental math strategies such as doubling, halving, and dividing by 10 to find the percents of some numbers. Write the percent as a decimal and then multiply by the number to calculate the percent of a number.
Eg. 14 1/2% of 60 = 0.145x60 = 8.7


Combining Percents

Adding percents can solve problems, for example; 5% + 6% = 11%.

To calculate the increase in a number, add the combined percents to the original number.
Eg. 15% of 100 = 0.15x100=15, 100+15=115
Or multiply the original number by a single percent greater than 100.
Eg. 115% of 100 = 1.15x100 = 115

Percents of percents can be used to determine amounts that result from
consecutive percent increases or decreases.

Percent review video:



In this unit, I did this percent scribe.
Here's a video and a link to help you learn more about percents.

Angel's Pay it Forward

Part 1

"Pay it Forward" is a movie about a boy named Trevor, and he wants to help needy people or people who have problems. First, he helps 3 people, and those 3 people will each help 3 other people and it will go on and on like a chain. The point he's trying to reach is that if one person can help a lot, imagine what a group of people can do.

Part 2

My group Julibella, Marie, Diorella, and Marilen decided to donate toys to the children in the hospital and gave cards we made saying "You've been hit by a random act of kindness, please return the favour and pay it forward! " along with candy canes. On December 18, 2010, we decided to donate toys to the hospital just to brighten up the children's days because we all know it's not fun staying at the hospital, sick, for days. Also, we decided to give out candy canes just to perform an act of kindness and to encourage people to pay it forward.



Part 3

On Saturday, December 18th my dad drove my group and I to Health Science Centre to deliver our red Santa bag full of toys. We went to the information desk to ask where we can drop it off, but instead a nurse came and took it for us. The nurse looked happy, and was thankful. I felt very good inside although it would've been better if we got to see the kids excited and happy about the new toys.

Afterwards, we went to polo park to hand out our candy canes and the cards that went with them. But then something unexpected happened that made us change our direction. The security cards went up to us and said we couldn't hand them out inside the mall. We were disappointed and felt let down. So, we went outside to the parking lot and placed the cards under the wipers. We didn't get to say "pay it forward" face to face to people but we still had it written on cards. Although it didn't go exactly the way we planned.. we still were happy that we performed an act of kindness and hopefully inspired others to do the same.

Part 4

Paying it forward is important because it helps a lot of people whether they're less fortunate or just doesn't have the greatest life. Imagine what a bunch of people can do if it only takes one person to make a difference like Trevor in the movie.

I also hope that our cards and the toys will make a difference and encourage others to pay it forward. This project made me learn to think more about others and know how blessed we are. Who knows where just a simple act of kindness can end up.

PAY IT FORWARD! :D

Angel's Percent Scribe Post

Questions:


1. Mary has a monthly salary of $1200. She spends $280 per month on her food. What percent of her monthly salary does she spend on food?












Mary's monthly salary that she spends on her food is 23%

I got 23.33 by dividing $280 by $12 .
I also rounded 23.33 to 23% .



2. Your restaurant can seat 150 guests. If 6 tables of 6 are seated, what percent of the restaurant seating is full?















24% of the restaurant seating is full.

I got 36 by multiplying 6 tables by 6 that are seated.
I got 4.16 by dividing 150 guests by 36.


3. My new golf club was $139.50 but it's last years model so I got a 60% discount. What will it cost me?













The golf club will cost $55.80.

Here's a video:



Here is a link .

Please inform me if i made any mistakes. (:

Pythagoras Textbook Number 15

#15 The coordinate grid shown was drawn on centimetre grid paper. What is the length of line segment AB? Express your answer to the nearest tenth of a centimetre.

















Answer:

















I got 2 cm for side a and i got 4 cm for side b because i counted the units AB were taking up on the graph paper vertically and horizontally.




PS:

I know i wasn't assigned this scribe but Thessa didn't have the answer so I just wanted share what i got if people were curious about the answer.. I'm not exactly sure if I'm right but there you go (: sorry harbeck !

Link: http://www.mathsisfun.com/pythagoras.html


Video:

Angel's Pythagoras Scribe Post

Scribe 3: Pg 91-93 #3, 8, 11, 16

3. For the triangle shown, Kenda wrote the Pythagorean relationship as r2 = p2 + q2. Is she correct? Explain.














She's not correct because the right formula would be q2 + r2 = p2 because the longest line is labeled p2 which is opposite from the right angle which makes it the hypoteneuse.










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



















No, because in this case a + b doesn't equal to 50. a + b = 60







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








16. Baldeep is building a wooden box for storing colored 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.














Links: www.mathsisfun.com/pythagoras.html
http://www.historyforkids.org/learn/greeks/science/math/pythagoras.htm

Video:



URL of textbook pictures:
http://ebook.mytextbook.ca/view.phpp=eef24f6cac95bfcf8e97648bbda1b669190f187a&c=2

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

Angel's Sesame Street Video

Group Members:
Marilen and Angel

Part 1:
Two term ratio; Compares 2 quantities measured in the same units. [ a:b ]
Three term ratio; Compares 3 quantities measured in the same units. [ a:b:c ]
Part to part ratio; Compares different parts of a group to each other. [ a:b, 2:5 ]
Part to whole ratio; Compares one part of the group to the whole group. It can be written as a fraction, decimal, & percent. [ b:all letters, 5:8 ]

Rate; Compares 2 quantities measured in different units [ 2km/2hr ]
Unit rate; A rate where the second rate is 1 [ 9 dollars/ 1hr ]
Unit price; Used when shopping [ 10 dollars/10mL ]

Proportional Reasoning; A relationship that says that 2 rates or ratios are equal. It can be written in fraction form. [ 2/3 = 6/9. (x3) ]

Part Two:
The Original Video
" Elmo's Song ";


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This video is about Elmo showing Big Bird and Snuffie a song he composed.

Part Three:
Our Remake of ' Elmo's Song '
" The Ratio, Rates, & Proportion Song "


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Our remake video was composing the definitions of Ratios, Rates, & Proportions into the tune of Elmo's song.

Angel's Math Profile

Hey, my name is Angel Malapit . I am a grade 8 math student, if someone asked me if I liked math I would say "not really" because math is my weak subject and I find it challenging at times and complicated to understand . The best thing I experienced in math class was in grade 1 and our class would be split in half and have a competition about adding or multiplying, then the losing team would be punished and had to do something for the winning team (as long as it was appropriate). It was a very fun game and still educational .

The best unit I studied last year in grade 7 were coordinate grids, I found it easy because you didn't really need to think hard and it was kind of fun . The unit I struggled the most was on integers, I kept getting confused on adding or subtracting opposite integers and all the positive and negative signs . What I will do to try not to struggle so much is to listen more attentively, study harder and longer, and ask questions about things I don't understand .

To be a successful math student in grade 8 I will do what I can or do anything extra to practice on what unit were on so I'll catch on quickly in math classes, and have an easier time on tests . I'll try to take risks and raise my hand when I have an answer or have any questions . This year I'm not looking forward to anything specific, I'm open to learning anything new . But I'm kind of interested in learning more of algebra .

I was a blogger last year and my favourite post I did was on the meaning of mean: http://room42math09.blogspot.com/2010/05/meaning-of-mean.html I liked this post because i met most of the expectations . I liked blogging about what we were studying in math class because it helped me observe the unit and really understand it and if I need a reminder or missed a class I could just easily check the blog and copy anything I missed . This year on the computer, I will be looking forward on making any math clips, and visiting more interesting and fun math websites .