Perimeter and Area Lesson 2.2 pages 61 65

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Perimeter and Area Lesson 2.2 pages 61 65

• What will we learn?
• Vocabulary perimeter, area
• What will we do?
• Use drawings and formulas to calculate perimeter
  and area of 2-dimensional (flat) figures.

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Vocabulary Journal

• Perimeter the distance around the outside edge
  of a figure, measured in linear units such as
  feet, inches, meters, or centimeters.
• Area the amount of surface the figure covers
  within the perimeter (inside), measured in square
  units such as square feet, square inches, etc.
• Lets do some examples in your math folder.

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Examples

• Perimeter - With your teams, use graph paper and
  tiles to create as many unique rectangles as
  possible with a perimeter of 16. Remember the
  sum of all the sides must equal 16 linear units.
• Area Now, lets count the number of squares
  inside each of your rectangles and write that
  value inside each figure on the graph paper. What
  values do you get? Why?

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7
1
4
6
2
4
5
3
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Formulas for Perimeter and Area

• Perimeter of a Rectangle linear units
• 2 times the length plus 2 times the width
• Formula P 2 x L 2 x W or P 2L 2W
• Area of a Rectangle square units
• length times width
• Formula A L x W or A LW
• Now, lets go back and use the formulas on the
  drawings weve created and compare results.

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Why should you care about perimeter and area?

• Maybe you want to paint your bedroom?
• How large of a house can you afford?
• How many friends can you invite over?
• What type of fence should you put around your
  yard and how much will it cost?
• What other examples can you think of?

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More interesting problems

• www.classzone.com - a direct resource for our
  text.
• Work with your team to solve the problem Im
  about to assign you. Display your solutions on
  chart paper in 2 ways-with a picture and with a
  formula. Be prepared to defend and justify your
  solutions.