# 905SPMath2011

## Sunday, May 6, 2012

### Patrick's 8 questions

x + 1 + 3(x) = 3(x + 2) + 4

x + 1 + 3x = 3x + 6 + 4

4x + 1 = 3x + 10

4x - 3x = 10 - 1

x = 9

Question 2: Jim is 4 times as old as Harry, and Harry is 8 years younger than Bill. The sum of the ages of Jim and Harry decreased by Bill's age, is 12. Find their present ages.

4(x - 8) + x - 8 - x = 12

4x - 32 + x - 8 - x = 12

4x + x - x - 32 - 8 = 12

4x - 40 = 12

4x = 12 + 40

4x/4 = 52/4

x = 13

Question 3: The sum of the angles of a triangle is 180 degrees. If the fist angle of a triangle is three times as large as the second, and the third angle is 5 degrees larger than the first, how many degrees are there in each angle ?

3x + x + 3x + 5 = 180

7x + 5 = 180

7x = 180 - 5

7x/7 = 175/7

x = 25

Question 4: The proceeds of a Junior High School dance amounted to $37.25. If the students paid 35 cents per couple, and non-students paid 50 cents per couple, how many of the 82 couples at the dance were students ?

35x + 50(82 - x) = 3725

35x + 4100 - 50x = 3725

35x - 20x = 3725 - 4100

15x/15 = 375/15

x = 25

Question 5: At what price per kilogram should a merchant sell a mixture of 50 kilograms of nuts if it contains 30 kilograms of almonds worth 40 cents per kilogram, and 20 kilograms of Brazil nuts worth 50 cents per kilogram ?

30(40) + 20(50) = 50x

1200 + 1000 = 50x

2200/50 = 50x/50

44 = x

Question 6: Mr. Jones withdraws $10 000 from a bank where it was earning 2% interest. He then invests part of the $10 000 in bonds paying 3%, and the remainder in stocks yielding 4% interest. By investing his $10 000 in this manner, he increases his yearly income by $140. How much has he invested in bonds ?

0.03x + 0.04(10 000 - x) = 0.02(10 000) + 140

0.03x + 400 - 0.04x = 200 + 140

0.03x - 0.04x = 340 - 400

- 0.01x/- 0.01 = - 60/- 0.01

x = 6000

Question 7: If pump A and pump B operate together, it takes 12 minutes to empty a swimming pool. By itself, Pump A can empty the pool in 20 minutes. How long would it take to empty the pool of only pump B was working ?

1/20 + 1/R = 1/12

(20)(R)(12)1/20 + (20)(R)(12)1/R = (20)(R)(12)1/12

12R + 240 = 20R

12R - 20R = - 240

- 8R/- 8 = - 240/- 8

R = 30

Question 8: For the Jones family, the trip from home to the cottage and back takes 3 hours. Going to the cottage they travel 50 km/h and coming back they travel 70 km/h. How far away from home is the cottage ?

D1 = D2

ST = ST

50x = 70(3 - x)

50x = 210 - 70x

50x + 70x = 210

120x/120 = 210/120

x = 1.75

D1 = D2

ST = ST

50(1.75) = 70(3 - 1.75)

87.5 = 70(1.25)

87.5 = 87.5

## Thursday, March 1, 2012

### Tianna Blog Post

- .75km

- 1.5min

6(x + o.75) = 6(5/6) 1.5

6x + 4.5 = 7.5

6x/6 = 3/6

x = .5km

Then you have to convert km into m

(.5)(1000) = 500m

The train is 500m

so..

3x = 8

3x/3 = 8/3

The next question

4y - 8 +8 = 15 + 8

read pp. 314 -318

CYU #1,4

Practise, Apply: ALL

Extend: only 4

and 28

8.3 Homework Book.

## Tuesday, February 28, 2012

### Trisha's Blog Post

**fraction**because Mr. Backe said to make it easier on us but decimal is optional.

**Homework:**

**Read pg. 304 - 310**

**Do the Show You Know**

**Check Your Understanding**

**Practice, Apply - ALL**

**Extend - Any 2 and #32**

**Chapter 8.2 in the Homework Book**

**AND the Yellow Sheet is due**

*tomorrow*.**You need to show cross multiply, divide by coefficient, multiply by the reciprocal and find the common denominator.**

*Mr. Backe won't take it if it's late so don't forget to do your homework.***Tianna**.

## Monday, February 27, 2012

### Shane's Blog Post

## Thursday, February 9, 2012

### Binomial by Binomial Mutiplication

## Wednesday, February 8, 2012

### Nils' Blog Post

**Multiplying Polynomials by Monomials**

**4 (2 + 4) = 4 (6)****= 24**

*4 (2 + 4) = 4(2) + 4(4)*

*= 8 + 16*

*= 24*

*5 (6-3) = 5(3)*

*= 15*

*5 (6 -3) = 5(6) -3(5)*

*= 30 - 15*

*= 15*

*2x (3x + 4)*

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

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

*= 6 x^2 + 8x*

*5 x (-2x +y -2)*Now I'll show you how to do the reverse. Finding the equation when you have the diagram.

Remember that the first part of the polynomial is on the left side of the diagram.

In this case ** -2x **is the first part.

**is the other part.**

*3x -4*So the formula is *-2x (3x - 4)*

Now we solve!

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

*= -6x^2 + 8x*

Some common mistakes people make when multiplying polynomials by monomials is...

1. Forgetting to look at the signs. Instead of making a number negative, you make it positive and vice versa

2. You forget to multiply all the terms in a polynomial. This one is kind of self-explanatory. REMEMBER TO MULTIPLY ALL THE TERMS!

Okay people! Here's the homework.

- Read Pages 264 -268
- Check your Understanding 2 and 3
- Practise 0dd or even
- Apply All
- Extend 2 of 3
- And the 7.4 Green sheet we got ages ago.
- And last but certaionly not least... MANGAHIGH!!! We are in a Fai-To!!!

If you have questions please ask. If not, then I bid you *adieu.*

Oh yeah I almost forgot. The next blog person is......... ANA LOPENA

## Tuesday, February 7, 2012

### Multiplying and Dividing Monomials

We started off the class by doing simple multiplication.

(3)(2)=6

(-4)(3)=-12

(-2)(-2)=4

(6)(-2)=-12

Then we started working on something more harder.

Tip: First number goes on the left side.

Second number goes on the top.

The last multiplication question

We then started dividing numbers.

-8/4=-2

Quotient goes on top.

Another question,

Another question,

Some questions you can solve, but can't model.

Examples:

Here is a video that may help you understand.

**HOMEWORK:**

**7.1 READ pg. 254-259**

CYU- 2

PRACTISE ODD/EVEN

APPLY: ALL

EXTEND 24, 26, 27

HOMEWORKBOOK 7.1

CYU- 2

PRACTISE ODD/EVEN

APPLY: ALL

EXTEND 24, 26, 27

HOMEWORKBOOK 7.1

**Don't forget to check MANGAHIGH!!**

**I Pick Nils to do the next blog**