## Wednesday, May 14, 2008

### Kiahna's Scribe Post

1. Mr. Enigma said, five less then one fourth of my age is 12 how old is Mr. Enigma?

Mr Enigma is 68 years old. Let x=his age

we are going to make x=1 becasue you can do that. they answer is

x/4-5=12

+5 +5

(4)x/4 17(4)

x= 68

2. Suppose you have $40 and you earn $7 per hour. How many hours must you work untill you have $131?

You would have to 28 work hours

7x+40=131

-40 -40

7x/7 91/7

x=28

3. Valley video charges a $15 annual fee plus $3 per movie for rentals. Last year, Jennifer spent $99 at the store. How many movies did she rent?

She rented 99 movies?

3x+15=99

-15 -15

3x/3 84/3

x=28

5.Suppose you are salesperson for Quark Compuer Company. Each month you earn $500 plus one sixth of your sales. What amount must you sell this month to earn $3000?

The amount he would have to sell was 15000.

x/6+500=3000

-500 -500

(6) x/6 2,500(6)

x= 15,000

6. For lunch Dregg had a hamburger and potato chips. The hamburger had 325 calories and each chip had 12 calories. If the meal had 541 calories, how many chips did Dregg eat?

He ate 18 chips.

12x+325=541

-325 325

12x/12 216/12

x=18

## Tuesday, May 13, 2008

### Robby's Scribe

Question 1:

The second of two numbers is 4 times the first. Their sum is 50. Find the numbers.

Ok, so, to answer this question, we have to find out which is the variable and have it equal 50. It also says "sum", so there is going to be addition in this question.

To find the variable, you have to read the sentence and find out what part of the question isn't told. But first, write the simple-sentence answer, which is just the answer in a sentence. You write this out first, then come back to it once u find the numbers.

10 40

The numbers are ____ and ____. (You can also write this at the end of the equation, which is what I'm going to do just to make it make more sense.)

"The second of two numbers"

This means that, in the equation, the second number will NOT be the variable, because if u read on..."is 4 times the first". This means it will be 4x, not just x, which is what we need.

So the first number will be x.

Remember, you have to have the "Let X = blahblah" somewhere in that equation, or u lose marks.

Moving on, 4x would be on the right side of the + sign, because it is the second number. The first number is x.

So the equation would look like this:

Let x = First number

x + 4x = 50 (what we have so far)

5x = 50 (combined like terms)

-- ---

5 5

x = 10

The answer to this question would be 10, 40.

SUBSTITUTE TO CHECK (this is to make sure you have the right answer)

x + 4x = 50 (must write formula)

10 + 4(10) = 50

10 + 40 = 50

50 = 50

x = 10

4x = 40 (this is very important too, before you write your answer into the sentence, you have to write out what the variable and term stand for in numbers, like above. Now you see why its easier to write the sentence at the bottom)

If the answer on the left side equals the right side (50 = 50), that means the number works.

Question 2:

(I will now be writing all the answers out with some info in brackets, if you don't get it, go back to Question 1: and read on how to get it.)

The larger of two numbers is 12 more than the smaller. Their sum is 84. Find the numbers.

"Larger of two numbers is 12 more than smaller"

The two other numbers would equal x, because nothing is told about them.

Let x = Smaller Number 1, Smaller number 2.

x + 12 + x + x = 84

3x + 12 = 84 (combined like terms)

-12 -12

3x = 72

-- ---

3 3

x = 24

Substitute to Check:

x + 12 + x + x = 84

3(24) + 12= 84

72 + 12 = 84

84 = 84

x+12 = 36

x = 24

x = 24

36 24 24

The numbers are ____, ____, and ____.

The answer would be 36, 48 [because 36 is 24 + 12 and 48 is 24 + 24 (2 x 24)]

Question 4:

The second of two numbers is 5 more than twice the first. Their sum is 80. Find the numbers.

"second of two numbers"

So the second number would be the term (number with the x or a or whatever letter next to it)

and the first number would be the variable.

Let x = First Number

"5 more than twice the first"

2x + 5

"sum is 80"

= 80

Now put it al together...

x + 2x + 5 = 80

3x + 5 = 80

- 5 -5

3x = 75

-- ---

3 3

x = 25

Substitute to Check:

x + 2x + 5 = 80

3(25) + 5 = 80

75 + 5 = 80

80 = 80

2x+5 = 55

x = 25

25 55

The numbers are _____, and _____.

25, 55.

Question 6:

Find two numbers whose sum is 92, if the first is 4 more than 7 times the second. Find the First number.

"Two numbers whose sum is 92, if the first is 4 more than 7 times the second"

so the second number is x, because it doesn't mention anything about it.

Let x = Second Number

(7x + 4) + x = 92 (brackets there to make it look simpler)

8x + 4 = 92 (combined like terms)

- 4 -4

8x = 88

-- --

8 8

x = 11

Substitute to check:

(7x + 4) + x = 92

8(11) + 4 = 92

88 + 4 = 92

92 = 92

x = 11

7x + 4 = 81

The first number is 11.

Question 8:

Together, a necklace and a bracelet cost $192. Find the price of each if the necklace costs 3 times as much as the bracelet.

"if the necklace costs 3 times as much as the bracelet"

This means the bracelet is x.

Let x = bracelet

3x = Necklace

3x + x = 192

4x = 192

-- ----

4 4

x = $48 ($48.00)

Substitute to check:

3x + x = 192

4(48) = 192

192 = 192

(now to find the price of a necklace and bracelet separately)

3x = 3(48)

= 144

x = 48

$144.00

+$48.00

--------

$192.00

The price of a bracelet is $48.00 and the necklace is $144.00.

### Romulo's Scribepost

*SCRIBE POST*So today in math we first went over this math sheet we had for homework called 7.3 Solving Geometric Problems. This took up about 45 minutes of the class and for the rest of the class we had time to do some of our homework which I'm scribing today.

Since no one has scribed anything about Algebra problem solving I'll post the 6 steps.*1. Simple Sentence Answer2. Unit Values3. In A Geometry Question DRAW THE SHAPE4. Whatever You Know Nothing About Is The Variable5. Identify Your Variable6. The Other Unknown Relates To The Variable*

Those are the 6 steps for sucess.

Here's an example on how you solve an Algerbra problem solving question.

The question is "A farmer uses 54 metres of fencing to enclose a rectanguler field. If the width is two metres less than the length, find the dimensions of the field.

1. Simple Sentence Answer

1. Simple Sentence Answer

For the simple sentence answer all you need is 3 words. Those 3 words are

The, are and whatever the question is asking you to find. So in this case your looking for the dimensions. So your simple sentence answer would be

The dimensions are _________ and _________

2. Unit Values

2. Unit Values

Unit values simply ask you to put whatever value you're working with in your simple sentence answer. So since we're working with metres you put "m" in your sentence. So it should now look like

The dimensions are _________m and _________m

3. In A Geometry Question

3. In A Geometry Question

__DRAW THE SHAPE__This one pretty self explanitory

4. Whatever You Know Nothing About Is The Variable

4. Whatever You Know Nothing About Is The Variable

For this one your variable(x or n or whatever you want) is the thing you have no clue about. So your first need to figure out who the playaz are. So the playaz are length, width and the perimeter. We know already know that the perimeter is 54 metres so it can't be the variable. We also know that the width is 2 metres less than the length so that leaves us with length which we know nothing about. So length is the variable.

length= variable

5. Identify Your Variable

5. Identify Your Variable

I don't really understand this step but I think this is the one were we have to remember to put let x= length somewhere or we lose a half a mark. So add

x= length

**6. The Other Unknown Relates To The Variable**

I dont really understand this one but I think it means if you have two unknowns they relate to the variable.

After all 6 of those steps you can finally start doing your work.

So all that was just an explanation on the steps. Now to get to the point of this scribepost. So the side I'm doing is the geometry side. The side that has the title

What's the Quickest Way for an Ant to Go From the Ground to the Tree Trunk__Questions__

1. The length of a rectangle is 3 times the width. The perimeter is 96 cm. Find the width and length.

2. The length of a rectangle us 5m greater than the width. The perimeter is 150m. Find the width and length

## Wednesday, May 7, 2008

### Jonah's Scribe

We went over the homework to see if we had any questions about it and solved it together. Then we learned how to solve a 2 Step Equation. Here are the steps:

1. Isolate the variable

2. cancel the constant (integer) using its composite to make zero pairs.

3. Balance

3a. cancel variable to (1.)

4. Substitute to check.

Here is an example:

But, we didn't just learn how to show in that way. We also were shown how to show it by using Algetiles. Here is the example used in class:

That is how we use Algetiles to show 2 Step Equations! That is all we did in class. don't forget to do the homework we got.

## Tuesday, May 6, 2008

### Jordan's Scribe Post

Then we had to make a T-Chart for the patterns we found...

the numbers in the "y" row start at 1 and go up by 2 each time..

(btw, the vertical lines through the strings are the cuts)

Followed by the T-Chart:

We found that the "y" row started @ 1 then increased by 3 each time

We found that the "x" row started @ 0 then increased by 1 each time

You have to multiply "x" by 3 then add 1 to get "y"

Algebraic Expression: y = (3n)+1

## Monday, May 5, 2008

### Marina's 2nd Scribe Post

Okay today in class, I volunteered to do a scribe post. I made a little slideshow on voicethread, i dont really know if i did it right so yeah...

P.s. I did this all on piant,so it ,might be messy.. didnt take me very long.

### Robby's Scribe

Like terms are Terms that have the same Variables next to them. Variables are letters that stand for unknown or given numbers. Like terms are 2 or more terms that can be combined to simplify the equation. Lets look at an example:

This right now is an algebraic math sentence. In algebra, you don't always have to find an answer to the question, that is, if you aren't told what the variable stands for. This is one of those occasions.

In algebra, you don't use all the operators you would use for non-algebraic equations. Like, for example, times (x). Because times has a operator that looks like a variable, it gets confusing (Like so: Variable x X x = x ...no it's not what you were thinking). So they removed it (they being those math geniuses that invented algebra). Instead of writing 5 x (x+2), you remove the x and assume its multiplication. And when multiplying a number with a variable, you write them next to each other (5x). This becomes a Term.

Back to the math sentence in blue above. An easy way when multiplying things in brackets and theres a variable in there is to multiply the outside number with the variable. So it would look something like this:

Like I said before, when multiplying a number with a variable, you put the variable on the right side of the number and it becomes a term. So 5x means Five groups of variable x.

The next part of the question is the +2. You would read this as positive two, because in algebra, you deal with integer numbers a lot. Now you have to multiply it with 5 now, because its still in the brackets, and if there's no operator between the brackets and number on the outside, you assume its multiplication.

Now, we multiply the 5 with the 2. 5 x 2 = 10 (note, I used the x symbol for multiplying because we aren't multiplying the terms, and this equation won't go in the final answer, only the 10 will)

The math sentence now looks like this:

This is a proper algebraic sentence. The terms should always be on the left side, and the non-terms, or integers, on the right. Now to to show you how to write this question using algebra tiles. But first, look at the different kind of shapes used to represent the parts of a algebraic-math sentence.

Now that we know what shapes I'll be using mean, on with the algebra-sentence. I'll simply show what the simplified answer to the algebra sentence near the middle of my scribe-post looks like with algebra tiles...

=

## Friday, May 2, 2008

### David's Scribepost

*Algebra Tiles**n, x)*squared, the long rectangles are the variable, and the little squares are the integer or the constant, it's just the number. There are two sides to Algebra Tiles, a white side, and a colored side, the white side means its a positive number, the colored side means its a negative number. So if your question is 3n+6 and you wanted to draw it out using Algebra Tiles, then it would look like this...

## Thursday, May 1, 2008

### Nathaniel's Scribe Post

Mr. Jerema gave us two charts the other day. We had to make a chart and a ratio table, describe the patterns in each row, describe the relationship between the two columns, make an algebraic equation to show that relationship, then find out what the 20th, 35th, and 99th diagram would be.

This is the first chart he gave us.

We had to make that into a chart.. like so

and into a ratio table..

3. Describe the patterns found in each row.

Well you can see that x, starts at 1 and goes up by 1, and y, starts at 1 and goes up by 2.

4. Describe the relationship between the two columns.

If you have the years over 10, and lets say you have 2. You would have to multiply it by two and subtract one to get y, since this works for all the years over 10.

C. Write and algebraic equation to show this relationship.

y=2x-1 x = years over 10

5. Predict what the 20th, 35th, and 99th diagram will look like.

We use the algebraic expression here, and having 20, 35, and 99 the years over 10.

note:re write the expression and fill it in.

20th

- 2x-1

- 2(20)-1

- 39

35th

- 2x-1

- 2(35)-1

- 69

99th

- 2x-1

- 2(99)-1

- 197

Now back to number one since instead of drawing the next two patterns, he said to find out the number of repairs for 7 and 8 years over 10.

7th

- 2x-1

- 2(7)-1

- 13

8th

- 2x-1

- 2(8)-1

- 15

And were done the car repairs! Onto Harbecks Training.

Then we had to make a chart, and a ratio table out of it..

3. Describe the pattern found in each row.

As you can see, x starts at one and increases by one each time, and y starts at 3, then adds 5, 7, 9 and adding so on by odd numbers.

4. Describe the relationship between the two columns.

If you have the number of weeks, to get the number of km's ran in total, you would have to multiply the number of weeks by itself, and subtract one to get the number of km's ran in total.

c. Write an algebraic equation to show this relationship.

y=x squared - 1 x=number of weeks

5. Predict what the 20th, 35th, and 99th diagram will look like.

20th

- xsquared-1

- 20squared-1

- 399

35th

- xsquared-1

- 35squared-1

- 1225

99th

- xsquared-1

- 99squared-1

- 9801

Then back to number one to find out what the 7th and 8th diagram will look like.

7th

- xsquared-1

- 7squared-1

- 48

8th

- xsquared-1

- 8squared-1

- 63

and your done!

### Angel's Scribe

- 3x+8 : Three times a number and eight
- 7x+5x : Seven times a number and five times a number
- 5(x+8) : Five times the sum of a number and eight
- 8-3x : Eight decreased three times a number

6. Seven decreased by four times a number : 7-4n

7. 9 less than 3 times a number : 9-3x 8. four more than eight times a number : 8x+4

This is my T-chartThe patter : x = Figure number, Starting with one going up by one.

y = Number of tiles, starting with four and adding three each time.

Here is my Graph

- x=Figure number
- y=Number of tiles
- The algebraic equation is 3x+7

### Vicky's Third Scribe

**Algebra Test 2**

1. 2x-9 = two

__times a number decreased by (less, reduce, take away, etc.) nine.__

__decreased by (reduce, and decreased ONLY) four times a number.__

__a number less (decreased, take away, etc.) than eight times five.__

__a number plus (increased, and, sum of, etc.) five times seven__

Write the following statements as algebraic expressions

__2/3 n + 6cm__

__3 (n+2)__

__9-2n__

__5n-4__

## Saturday, April 26, 2008

### Vicky's Bob

**What I Know About Rectangular Prisms**

**, also known as**

__Rectangular Prism____Cuboid__(the shape), is a solid 3D (3-dimensional) object which has six faces, Top, Bottom, Left, Right, Front and Back. Each opposite faces of a rectangular prism are equal, for example Top is equal to Bottom, Left Side is equal to Right Side, and Front is equal to Back.

A

**Net is a disasemble box**, or an open box. Its very usefull when you want to find the area of each faces.

This is an old voice thread that I have used on my second scribe post. Yes, I have finally changed it to public, sorry for the

*technical difficulties~.*Teeehheeee.

## Thursday, April 24, 2008

### emilyr's bob

A rectangular prism is a 3d object that has length, width and height.

When its flattened it is called a Net. A net is just how you look at the prism when you open it all up. The net helps you get the surface area.

l= length

h= height

w= width

To get the surface area you can find the area of all the parts (top, bottom, front, back, left side and r side) then add them all up. The easier way is to use formulas.

The formula for top and bottom is: LxWx2.

The formula for front and back is: LxHx2.

The formula for the two sides is: WxHx2.

After you find the area for those you add them all after. After you add them you have you're surface area. The surface area is usually cm² or something².

Another thing I learned was to get the volume. The volume for formula is LxWxH or BxH. The B stands for Base and the H stands for Height.

The volume is usually something³

For examples look at my scribe post

## Wednesday, April 16, 2008

### Angel's Scribe Post

**Cylinders and Circles**

**All about the radius and diameter :**In class we were told that radius is the distance from the centre of the circle to the edge and you can get it by dividing the diameter because the diameter is double the distance of a radius going from one edge of the circle to the other. The formula to get the diameter : d=2r. meaning the diameter = 2x the radius.

**The circumference : **The circumference is the distance around a circle. You can get this by 2Pi r (2 x pi x r) pi 2r or pi x diameter.

**Cylinder :** In class we learned how to make a net of a cylinder.

**>PLEASE DO NOT DRAW A PEN15<**

also make sure that the circles are the same size.

W = Height

**FORMULA**

A = Pi R2 C = Pi D

A = 3.14 x 5cm2 C = 3.14 x ??cm

A = 3.14 x ??cm C = 3.14

A = ??cm2

Total surface Area : ??cm2+??cm2+??cm2 = ??cm2

## Tuesday, April 15, 2008

### Nathaniel's BOB

I have learned about length, width and height of a rectangular prism.

I have also learned that you can open it up to make it flat. It is called a net! Each side still is the length, width, and height.

l=length

h=height

w=width

To find the surface area you have to add up all the sides squared.

If you had a 2x2x3 prism, you would have to multiply..

LxHx2

LxWx2

HxWx2

LxHx2 is the front and back of the prism.

LxWx2 is the top and the bottom of the prism

HxWx2 is the left side and right side of the prism.

After you add it up you should have the surface area.

To find the Volume of a rectangular prism, you can just do Length x Width x Height!

Volume is how many cubed (insert measurement here example cm) can fit inside the prism.

If the length = 2cm

width = 2cm

height = 3cm

You would do 2cm x 2cm x 3cm to get the volume

The volume would be 12cm cubed.

Ps: hooray 200th post!

### Jonah's bob

We learned about getting the Surface Area and Volume of rectangular prisms. But the step we always do is making a Net.

Surface Area:

There is a lot of work to do before you can actually find out the surface area. You have to find out the area of each of the shapes. The top, front, and the left side. You only need to find out only one of each shape because each one has a pair. The right and left sides, the front and back, and the top and bottom.

The formula for figuring out the top and bottom is LxW (length x width). Since you only need to find out one of each shape all you have to do is then multiply it by 2. So it would be lxwx2 to equal the answer with a exponent of 2 (squared). E.g 3cm x 2cm x 2 = 12 2 cm.

The formula for figuring out the sides is HxW (height x width). Again, since you only need to find out only one side all you have to do is multiply it by 2. So then it would be hxwx2 to equal the answer with an exponent of 2 (squared). E.g 6cm x 2cm x 2 = 24 2 cm.

The formula for figuring out the area for the front and back is HxL (height x length). Since you only have to find out one of the shapes all you have to do is multiply the first answer by 2. So then it would be hxlx2 to equal the answer with an exponent of 2 (squared). E.g 6cm x 3cm x 2 = 36 2 cm.

Then you add all the numbers to together to get the total surface area. The exponent for surface area is always 2.

Volume:

Figuring out the volume for a rectangular prism is some what harder that find the surface area. But in some ways it is easier because you are only figuring out what is the number of the inside of the shape. There are two formulas of finding the volume.

Area of the base x Width is one of the formulas. First you find out the measurement of the base. Then you multiply that by the width because that is how many base numbers you have. E.g Base number = 15 cm 2 and the width = 3 cm. So it would be 15 cm 2 x 3 cm= 45 cm 3.

The second formula is LxHxW (length x height x width). You first find out the measurement of the length, width, and the height. Once you do then you multiply them all together. E.g L = 5 cm

H = 10 cm W= 3cm. 5cm x 10 cm x 3 cm = 150 cm 3.

The exponent for volume is always 3.