David's Scribepost

Algebra Tiles

Algebra tiles are ways of showing algebra. The big sqares are the variable (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...

Theres something else that comes into effect when we do this, and its Zero Pairs. Zero pairs are when you have a positive and a negative, and they cancel eachother out.

It's like you owe money if there's a negative, and the positvive is how much money you have. Thats just one good way to try and understand intergers.

Afrer that we just did a bunch of questions and figured them out using algebra tiles, one of them would be 2n-6+4n-2+6-n. So how would you draw that out? Now if you can't tell where to start and which sign belongs to what, then try making the catapiller, start at the first number / opperation and circle to the next one.

Now thats nice but we want to group them.

We can get rid of some by finding zero pairs!

and we're left with 5n-2

And thats how you use Algebra tiles. We had homework too, 3 pages of it.

^ ^ On this one you only need to do up to question 18...^^

Good luck finnishing! I'm sure there's going to be more work.

Nathaniel's Scribe Post

Patterns 2!!

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

Algebra Test #1

For the first part of the test we had to write the following expressions in words..

1. 3x+8 : Three times a number and eight
   
2. 7x+5x : Seven times a number and five times a number
   
3. 5(x+8) : Five times the sum of a number and eight
   
4. 8-3x : Eight decreased three times a number
   

For the bottom of the first part of the test we had to write the following statements as algebraic expressions..

5. 9 centimeters less than three fourts of length x : 3/4x-9
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

For the second part of the test we had to make a t-chart, graph and figure out the algebraic equation for the following problem ..
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

How to get the answer

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

Vicky's Third Scribe

Today in class, I volunteered to do a scribe post for this month on algebra test number 2.

This is what the Algebra Test 2 looks like.

Algebra Test 2

Write the following expressions in words.
1. 2x-9 = two times a number decreased by (less, reduce, take away, etc.) nine.

2. 10-4x = ten decreased by (reduce, and decreased ONLY) four times a number.

3. 5 (x-8) = a number less (decreased, take away, etc.) than eight times five.

4. 7(x+5) = a number plus (increased, and, sum of, etc.) five times seven

Write the following statements as algebraic expressions

5. 6 centimeters more than two thirds of lenth x = 2/3 n + 6cm

6. three times the sum of a number and two = 3 (n+2)

7. nine decreased by two times a number = 9-2n

8. four less than five times a number = 5n-4

The following graph shows the first four terms of a pattern.

A) Create a chart that shows the first 10 terms of the pattern.

B) Write the algebraic expression for the relationship between the hours spent walking and the number of kilometers walked.

4n - 1

y is km walked

x is hours

C) Using your algebraic expression, determine how far they could walk after 50 hours.

4n-1

4 x 50 huors - 1 = 199 km

Done!~ Teehee!~

Vicky's Bob

What I Know About Rectangular Prisms


Rectangular Prism, also known as 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.

How to find the volume of a rectangular prism.

emilyr's bob

What I Know About Rectangular Prisms ;
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

Angel's Scribe Post

Cylinders and Circles

Today in class we learned about the circles and its radius, diametre, and circumferance. Later on during class we also learned how to find the area of a cylinder.

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.

L = Circumference
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