Kathleen's Scribepost for February 16, 2011

Multiplying Binomials by Monomials

Today, we started out with an equation to solve.

- ( x + 7 )

How to solve:

= -1 ( x + 7 )

= -1x + (-1)(7)

= -x -7

Next equation:

2(3x + 4)

Solve:

= 2(3x)+2(4) or 3x+4+3x+4

= 6x + 8

This is called distributive property.

The trick to answering an equation is to look at the signs very carefully.

Signs will always confuse you.

(-)(-) Two negatives makes a positive.

(-)(+) One negative makes a negative.

(+)(+) Positives makes a positive.

Example:

-2 ( 3x - 4 )

= -2(3x) + -2(4)

= -6x - 8

2x ( 3x + 4 )

= 2x(3x) + 2x(4)

= 6x ² + 8x

Another way to write this is:

(2)(3)(x)(x) + (2)(4)(x)

Which equals the same thing.

Now a model can be shown:

Another equation is:

-4x (2x - 3y +5)

= -4x(2x) + (-4x)(-3y) + (-4x)(5)

= (-4)(2)(x)(x) + (-4)(-3)(x)(y) + (-4)(5)(x)

= -8x ²+ 12xy -20x

Now one more step is missing; which is the equation has to be in alphabetical order for final answer.

= -8x ²- 20x + 20xy

Homework:

Read pages 264-268

CYU 2 & 3

Practice Odd or Even

2 Apply

Extend - 19 & 20 or 20 & 21

Homework Book 7.2

Extra Practice 7.2

Kenneth's scribepost for February 14 2011

Hello classmates :) This is in period 3 Day 1 cycle Math on February 14 2011

Multiplying and Dividing Monomials

Today Mr.Backe gave us a question when we were seated. His question to us was

- (6x +7)

- notice that the "-" is spaced out because right there is the "1" beside it, You just don't see it but its there because mathematicians are lazy and they leave a space beside the "-" and the bracket.

Also notice that this is a binomial question because you'll be doing this on a quiz I think.

- (6x +7) = -1 (6x+7)

= -1 (6x) + (-1)(+7) (second step)

= -6x -7

Notice the (+) is placed there as well as (-1) at the second step. It was put there because you know that by doing the first step the (-1) stays the same because your adding the +7 and that is why -1 is beside +7 (hope I explained it well enough for you guys to know).

The "+" is moved down to the second step because your adding the other side (I also hope I explained it well). (-1)(+7) multiply each other just letting you know and the "-" stay "-".

The third step is the answer because the -1 and 6x "fuse" together to make up a -6x and -1+7 equal up to a -7 so yea the answer is -6x -7. That is called Distributive Property which you learned but I'm typing it down anyway so yea.

Distributive Property means that we distributed the negative one over both terms of the binomial.

More questions Mr.Backe gave us and that we learn how to do it is 2 (2x)

The 2 (2x) means that you have "2" groups of "2x" meaning those tiles, but I cant draw or computer it because I don't know how you guys would see it, but I'll give out the answers

2 ( 2x) = 4x because your multiplying them

More questions Mr.Backe gave us which took us an easy time but sometimes hard for others like Asham just kidding. Just giving the answer.

-3x (2x) = (-3x)(2)(x)(x)

= -6x squared

2(2x) = (2)(2)(x)(x)

= 4x squared

3x(2x) = (3)(2)(x)(x)

= 6x squared

-3x(-2x) = (-3x)(-2x)(x)(x)

= 6x squared

Exact procedure but different statement.

Mr.backe added a "y"

(2x) (2y) = (2)(2)(x)(y)

=4xy

your just adding in the "y" variable

(2xy) (2x) = (2)(x)(y)(2)(x)

notice that I'm doing it in the exact order and now your finding "like" terms

= (2)(2)(x)(x)(y)

= 4x squared y

(3x) (3xy) = (3)(x)(3)(x)(y)

= (3)(3)(x)(y)

= 9x squared y

Now its negative 2

(4xy) (-2xy) = (4)(x)(y)(-2)(x)(y)

= (4)(-2)(x)(x)(y)(y)

Notice that I'm highlighting the 4 and negative 2 because the negative sign stays the same even if the 4 is a positive (hard to explain) -_-

= -8x squared y squared

Mr.Backe taught us how to divide polynomials and this is the question he gave us

6x over 2 = 3x, In order to find that answer you gotta do this,

Start with the question, 6x over 2 then you use the procedure (which I mentioned)

6x over 2 = 6 (x) over 2 (x) Multiply them and you get 3x squared but you can just basically cross the answer and the denominator to get the original number (6x)

Here's an easy one Mr.Backe gave us

6x squared over 2x

= 6x(x)(x) over 2(x)

= 3x

9x squared over 3x = 9 (x)(x) over 3 (x)

= 3x

Your dividing the number and your crossing out one "x" leaving out one x in 9, the denominator is the same so its 3x because 9 over 3 is 3.

HWBK

-Get Ready

TxtBook

-7.1

-p.253-259

-cyu #1+2

-extra practise 7.1

-self check ALL OF IT!!!!!!!!!!, oh and don't forget to do them in case you missed what's yesterdays homework.

If I have made any mistakes please correct me

Next scribe is John Pangan ! :)

Alex`s scrbe Post for January 26/10

For Math today, we got a few problems to do.
1.A banquet hall charges $100 for the hall and $20 per person for dinner.
(a) Create an equation to model the relation
This equation would be c=100+20p because there is $100 plus the $20 and p is for people.
(b) Complete the table of values
l
After it is completed it should look like this because when you use the equation, depending on the number of people, you multiply however many people there are in the column at the end of the equation to get the total cost
.
(c) Graph the relation

This is the first graph before I graphed.

This is the graph once I have graphed the points from the table.
(d) use the graph to determine the cost of 22 guests.

I put points in between 20 and 25 to get to 22 and then I made a line going up to the line that connects all of the points, and then I made the line go to the left to see the total cost of 22 guests which is $540.
(e) Verify your answer to (c) by using the equation to calculate the cost of 22 guests.
c=100+20x22
20x22=440
440+100=$540.
(f)How many guests could you pay for with $1100?Use extrapolation or the equation to arrive at your answer.
We are going to use extrapolation, the equation, and a chart the show the answer.
First, we will use the equation.
c=100=20p
1100=100=20p
1100-100=100-100+20p
1000/20=20p/20
50=p
Second, we will use the table.

And third, we will use extrapolation.

It shows that 50 people would equal $1100 by following the bold line.
The homework is read pages 220-225, cyu#1, practise c/e, apply any four, extend any 1, and do 6.2 in the homework book.
Sorry that the graphs are not just like the ones in the worksheet.
The next scribe is Kenneth

Hello fellow classmates, this the blog for January 20, 2011.

As you know we received an assignment on making charts for the outrageous flower costs. We did these charts and realised that something was wrong. The rate seemed to go down like a slope instead of going up.This was called a negative slope. Negative Slope refers to a mathematical formula rise. Y going up and x going across.
over
(0,10) (8,2)
x, y x, y going down by 2 and moving to the right by 1. so this would make -2 divided by 1. -2. So the negative slope is -2.

Next we learned about the equation y=m x + b
m being a slope, and b the intercept of when the rate Finally wher y intercepts the origin.( 0 ).

Here is the rest of the work we did: y = 5 over 2 (x) + 20
y= 5 over 2 (1)
2 y =5x 37
2y = 32 -5x
2y = 37 - 5 (1)

2y over 2 32 over 2 y = 16

Linear Relations Jan.19.2011

Hey guys so Today in class we learned about Linear Relations ...

1) The first thing we did in class was copy some words down so if you didn't get these words here are all that we wrote during notes...

coefficient

variable

constant

linear relation

linear equation

interpolate

extrapolate

2) So the next thing we did was do some questions that Mr. Bake gave us and the questions were about the flowers (red roses, pink roses, and carnations) and we had to spend all of the money to figure out how much flowers we would get at the end and how many possibilities we could do differently...

All flowers and No change all money has to be used

1. pink roses $2.00 carnations $1.00 and you only gotta use 10 dollars

So there were 6 possibilities for this answer and here they are...

Pink roses Carnations Money

5-0 10

4-2 10

3-4 10

2-6 10

1-8 10

2. red roses $5.00 carnations $1.00 and this time you only gotta us 27 dollars

So there were also 6 possibilities for the answer and they are...

Red Roses Carnations Money

5- 2 27

4- 7 27

3-12 27

2-17 27

1-22 27

0-27 27

3.red roses $5.00 pink roses $2.00 and you only gotta use 37 dollars

So there were only 4 possibilities

Red roses Pink roses Money

7-1 37

5-6 37

3-11 37

1-16 37

So you can see that when you look at these 3 questions there is also a pattern in them because in question 1 you can see that the graph is ascending and descending orders and they go up by 2's and down by 1's....

For question 2 the pattern is going up by 5's and going down by 1's

For question 3 the pattern for this question is that is it going up by 5's and down by 2's

.... So yeah here is what we did in class today and just a REMINDER that you guys gotta hand in your stash-it on Friday to make any changes ( i think) and the computer assignment with :

Words

Definition

Picture

Example

Non-example

AND!! for homework you guys gotta finish the graph Mr bake gave us!!

Well since no one or I mean sometimes people who do the scribe maybe will be chose tomorrow I guess but yeah thanks for reading my scribe post!!

P.S please correct me if I made any mistakes but anyway see ya!!

Raquel's Scribepost for January 6 2011!

Today, In math class Mr.Backe gave us some words that we have to find the definitions for
- Coefficient
-Term
-Variable
-Polynomial
-Monomial
-Binomial
-Trinomial
-Degree of a Term
-Degree of a Polynomial
-Like terms
-Algebra

We also learned about " like terms. "
Examples:

There are other examples.. but they take to long to do..

We learned what to do with monomial, binomials, trinomial with a chart:

-The chart is kind of ugly.. sorry. Remember to do your homework!!

Kathleen's Scribepost for December 10, 2010

Today in math : Classifying Triangles

HOMEWORK 

4.3 Extra Practice 
Textbook ; Practice and Apply ODD OR EVEN, Extend 18 and 20. 
Oh, sorry for all the pictures and not much words. Just got lazy with paint. SORRY! 

AND I PICK PAULO FOR THE NEXT SCRIBER. HAVE FUN.