Thursday, October 28, 2010

Prime Factorizaton and Square Roots

Show You Know: (page 82)

Write the prime factorization of each number. Which number is not a perfect square? Explain how you know.

prime factorization- a number written as the product of its prime factors.

45 is not a perfect square.
Textbook Questions: 1, 5, 10, 15 (pg. 85 & 86)
1.) Explain how to square the number 7.
answer: To square the number 7 you multiply 7x7=49.
5.)a.) Determine the prime factorization of 4.
b.) Is 4 a perfect square? Explain.
c.) Draw the square and label its side length.
a.) The prime factorization of 4 is 2x2=4
b.) 4 is a perfect square because its square root is a whole number with no decimals. ( 4's square root is 2)

10.) Determine the area of a square with each side length.
a.) area: s x s= s squared
20 x 20= s squared
20 x 20= 400 square units
b.) area: s x s= s squared
17 x 17= s squared
17 x 17= 289 square units
16.) Determine the value.
a.) square root of 9.
b.) square root of 25.
c.) square root of 1600.
a.) The square root of 9 is 3. (3x3=9)
b.) The square root of 25 is 5. (5x5=25)
c.) The square root of 1600 is 40. (40x40=1600)

Here is a link to help you with prime factorization.

Here is a video on prime factorization:


  1. Good post Emily. Your post was very good because it had a video, link, and a few images, too. It was also a good post because it was very detailed and gave all the answers to the questions you were supposed to do (don't worry, I didn't copy). However, the formula for area is A=s squared, not SxS=S. Also, you might want to put a better title than 'Scribe 1'. Otherwise, good post.

  2. Great job Emily. Your post is great. I liked how you used colors, also your video explained more about factor trees and your link was great too. Although your second picture got me confused. Guys correct me if im wrong, I think its suppose to be 2 squared not 4 squared. The side is 2 times 2 so the area is 4. If you put 4 squared then the side would be 4 times 4 the area would be 8.

  3. Oooohhhhh... Nvm. I get it now :). Sorry..

  4. Good Job Emily! Your scribe was really neat and easy to read. But there was one part i got last at.. Next time you should of made your pictures colourful and stuff. But other than that, good job!

  5. Good job Emily! I like the pictures you put in. Next time, try adding more color.

  6. Great job Emily! I like how you explain your work, I think it's very understandable! I like how you put an images, link and video! Keep up the great work!