Monday, March 22, 2010

Area

Area
-the space a shape takes up
-described in square units eg. 4cm²

Review
Area of square or rectangle
Length x width
A=lxw

=6x2

=12cm²



Parallelogram
Base x Height
eg. the base 10cm and the heght is 5 cm

A=bxh
A=10x5
A= 50 cm²

Finding the Area of a circle

Use pieces of circle to create a shape very close to a parallelogram.


Close to parallelogram

H=Radius
B=½ circumference
Ap=bxh
Ao=2 pi r ÷2 x r
Ao=pi xrxr
The simple formula is Ao=pi
*Sorry the pi symbol doesn't work.
Find the Area of a circle with the radius of 10m.Show formula and work.

Ao=pi
Ao=3.14xrxr
Ao=3.14x100
=314m²

Find the Area of the following circles
the first circle has the radius of 8cm
the 2nd circle has the radius of 14.8m

Ao=pi r²
Ao=3.14x8x8
Ao=3.14x64
=200.96cm²

Ao= pi r²
=3.14x14.8x14.8
=3.14x219.04
=687.79m²

To find the Area of a circle,and the question gives you the diameter.
You should divide it into 2.After you find the quotient use formula to answer the question.

Check out this site:
http://www.mathplayground.com/
Check out this video

22 comments:

  1. GOOD JOB KAREN -(CLICK:)!!! Your scribe is almost perfect but next time try not to use light colours. BUt overall you did a fantastic job! KEEP UP THE GOOD WORK!!!

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  2. Great job Karen, i really liked it how you put a different arrays of colors and videos awesome job !

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  3. Awesoome Joob Buddy! I like the videos and the pictures you added. Next time, try to not use light colours. Keep up the good work buddy (:

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  4. Good job!! A tip for next is to avoid using bright colours because it is hard to read.

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  5. Great Work Karen! (:
    I really liked the colors, pictures and videos you added in. your scribe is very neat and organize I think that you didn't miss a thing on what we did today, as others said use brighter color, overall you did fantastic job.

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  6. and thank you for putting the website. (:

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  7. nice job karen keep it up

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  8. FANTASTIC JOB CLICK ;) your scribe is very well organized and almost as perfect, I agree with Bennette with your use of colours. Other than that, you did a magnificent job! KEEP IT UP CLICK :D

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  9. MAGNIFICENT JOB KAREN!I liked how you added videos and it is very well organized.However, next time do not put light colours because it is very hard to look at.Besides that you did a fantastic job.Keep it up!:)

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  10. Good job. I liked the video you posted.

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  11. Great job Karen! I liked how you added in a video & pictures. Next time, try not to use bright colors. Overall, you did a great job!

    ReplyDelete
  12. good job karen! Keep up the good work!

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  13. Good Job Karen, it's well organized, nice video and good job putting a link. Keep up the good work !

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  14. Great job Karen!
    I liked how you added in video and pictures. Next time, try not to use bright colors. Overall, you did a great job!

    ReplyDelete
  15. Great Job Karen, you used many colors and videos (:

    ReplyDelete