Stretching & Shrinking Scale Factor

Stretching & Shrinking Wrap Up 2.3 Bt

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Scale Factors

Today in class we took some notes on scale facors. We found the shapes that were similar and then we found the difference between the similar figures. The rectangles that were similar were L, J, and N. The difference from L to J was 2, the difference of the area was 4. The difference from J to L was 1/2, the difference of the area was 1/4. The difference from L to N was 3, the difference of the area was 9. The difference from N to L was 1/3, the difference of the area was 1/9. the difference from J to N was 1 1/2 or 3/2. The difference from N to J was 2/3.
We also found the difference between triangles. The triangles that were similar were O, R, and S. The difference from O to R was 2, the difference of the area was 4. The difference from R to O was 1/2, the difference of the area was 1/4. The difference from O to S was 3, the difference of the area was 9. The difference from S to O was 1/3 the difference of the area was 1/9. Tghe difference from R to S was 1 1/2 or 3/2. The difference from S to R was 2/3.

Scale Factor

Today in class we learned about scale factors. A scale factor is the number that you multiply x or y by. For example, 3x, 3y, the 3's are the scale factors. The scale factor can be the number of times you multiplied the x or y. Also in class today, we did a geometry sketchpad. It was with a figure of zug and then a copy of zug (image). We also learned how to make the other image move up and down and to the side. If you add to the y axis the shape moves up and if your subtract from the y axis the image moves down. If you add to the x axis the image will move to the right. If you subtract from the x axis it moves to the left. We experimented with the images and found out some cool things.

Finally, we reviewed how if you multiply the x and y axis by the same thing you we make the image bigger or smaller. The image will also be the same. If you multiply two different numbers then the image won't be the same.This is Daily Scribe

That is what we did on Thursday december 10, 2009!!

Stretching & Shrinking Zug

Zug Bt

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Daily Scribe by Eli L.

Today in class, we learned that if you add or subtract to the verticies of a shape, it will move. When you add to the "x" axis, the shape moves right. If you subtract from the X axis, then the shape will move to the left. When you add to the Y axis, the shape moves up. If you subtract form the Y axis, the shape moves down. We also learned that if you multiply by a fraction or decimal, the shape gets smaller. The last thing we learned was that if the X and Y coordinates are multiplied by the same number, the shape stays similar, it just gets bigger. When there are different numbers, the shape will not be similar.
BY ELi L

Stretching & Shrinking problem 2.2 Hats off to the Wumps continued

Stretching & Shrinking 2.2 Summary + Tests For Similarity

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Math Blog Post

Today, we continued to work with the wumps. We grouped up and compared each wump, Mug, Glug, Bug, Zug, and Lug. We compared them mathmaticly, looking at things each wumps hieght, width, and side lengths. After we did that, we found that Glug and lug were imposters of mug because their lengths weren't stretched evenly. Zug and Bug aren't imposters because their lengths are evenly stretched out, meaning they were 2 or 3 times than the original mug.

After we found out the area of the non-imposters mouths. We knew Zug was twice as big as mug and bug was 3 times as big as mug. The areas don't follow that rule though. Mugs moth area was 4 units sq., zugs was 16 units sq., and bugs, was 36 units sq. That rule for finding the area is multiply the hight and width and that number is how many times bigger the wump is than the original, mug wump.

Math Blog Post

Stretching & Shrinking problem 2.2 Hats off to the Wumps

Stretching & Shrinking 2.2 Bt

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Enlarging Images by Percents

If you want to enlarge something by a percent, the perimerter and the side length will be increased by that percent, but the area will be different. For example: if you want to increase a square of 16 sq in. by 25%, you would need to find the side length so you can find the perimeter. You can multiply that by 4 since there are 4 sides of a square. The side length would be 4 sq in. for the original figure so the perimeter would be 16 sq in. To find the perimeter of the figure enlarged be 25%, you enlarge the sides by 25%. The enlarged figure's side would be 5 sq in. so the perimeter would be 5x4=20 sq in. To find the area, you would multiply the base and the height. That would be 5x5=25 in. sq. Don't forget about Mug Wump, Zug Wump, Lug Wump, Bug Wump, and Glug Wump, the video game! Remember that on the coordinates of the game characters, "start over" means literally pick up your pencil.

Stretching & Shrinking problem 2.1 Introducing the Wumps

Stretching & Shrinking 2.1 Bt

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Daily Scribe

Today in class, we learned about area, perimeter, percents and about corresponding sides and angles. We learned that to find the area of a square, rectangle or parallelogram you multiply the base by the height. Multiplying the length by the width is the same as multiplying the base by the height. We also learned that to find the area of a triangle you multiply the base by the height but then divide by two. We learned that the base and the height always meet at a right angle. For area, you want to take the height of a parallelogram or a triangle instead of taking the length of the sides, for the height. We learned about area is class.

Today we also learned about perimeter. To find the perimeter you add the length of all the sides together. In this case you do not take the height of the sides but you take the length of each side.

We learned today, how to find the length of the sides of an image from the original. There was one copy that was 75% and the other copy was 150%. We had to figure out the length of the sides of the images, using the lengths of the sides of the original. We also had to compare the length of the sides of the images to the length of the sides of the original, the angle measurements of the images to the original and the perimeter of the images to the original. Today we learned about percents.

Finally, we leaned about corresponding angles and sides. We learned that corresponding angles and sides are either angles or sides that are in the same place on each shape.

We learned about area, perimeter, percents and the definition of corresponding on December 4, 2009.

Scaling Up & Down

Here are our notes from Stretching & Shrinking Problem 1.3.

Stretching & Shrinking Problem 1.3 Bt

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Similarities

Today in class, we practiced drawing things that are similar, and we discussed what similar means. To be similar, is to have things in common. When an image is redrawn in a similar way, the first image that is referred to that is used to draw the second drawing is known as the original drawing. The second image that is similar to the original drawing is known as the image drawing. Today in class, we worked on a figure activity, and some things that were similar between the two shapes, is the general shape, the degrees of each angle, and the vertices. What was different about the two shapes, is the lines of each angle get longer or shorter, the size of each shape, the area of each shape, each length of the image is twice the length of the original, and the perimeter of each shape. This is what we did in class on December 3rd, 2009.

Stretching & Shrinking

What is the same in similar shapes? What is different? Here are our notes from today as we begin to explore similarity.

Stretching & Shrinking 1.2 Bt

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Today in math we reviewed for the test on GCF (greatest common factor), LCM ( least common multiple), adding, subtracting, dividing, and multiplying fractions and mixed numbers.

To find the greatest common factor of two numbers you figure out the prime factorization for each number. For example: 40 and 60.

40- 2*2*2*5

60- 2*2*3*5

then you find all of the factors that the two numbers have in common.

2 2 and 5 so the GFC is- 2*2*5 or 20

To find the least common you...

1. write the prime factorization

2. Use the greatest power of each factor

3. Write the LCM as a product

For example: 12 and 8

STEP 1

12- 2*2*3 =

8- 2*2*2- 2

STEP 2

2 to the second power * 3

2 to the third power ARE = TO 2 TO THE THIRD POWER *3

STEP3

two to the third power * 3 =

8* 3= 24

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

To add fractions you have to find a common denominator. For example: 1/2 + 3/4=?

To find the common denominator you could multiply both denominators. Or you could divide the

denominators. In this case 2 goes into 4 evenly so the new fractions would be: 2/4 + 3/4=? Now

you add across but keep the denominator the same. so the answer is 5/4 or 1 1/4.

The same thing applies for subtracting fractions.

To multiply fractions all you do is multiply across.

To divide fractions, you keep the first fraction the same and flip the second upside down. For

example: 3/5 divided by 3/4, you keep the first fraction and change the second on to its

reciprocal 4/3 and change the division sign into a multiplication sign.

To add mixed numbers you do the same thing, find the common denominator and add the

add the fractions and then the whole numbers. Simplify if possible.

Do the same to subtract.

To multiply change the numbers into improper fractions, multiply across and then simplify.

Example-2 3/4 * 1 1/5 = 11/4 * 6/5= 66/2o= 33/10= 3 3/10

To divide change the mixed numbers into improper fractions. Then keep the first the same and

change the second one to its reciprocal. change the division sign to a multiplication sign.

Then simplify.

3 1/4 divided by 1 1/2= 13/4 divided by 3/2= 13/4 * 2/3=26/12= 2 1/4

=D =P =] =O