Chapter 7 Similarity

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Chapter 7 Similarity

• Big idea showing two triangles are similar

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• 15 minutes of D.E.A.R

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Agenda

1. DO NOW center point of rotation is P (1, 1), the
   shape to rotate 40 degrees has the ordered pairs
   A (5, 1), B (8, 1), and C (3, 3)
2. Launch grab bag (are the objects similar)
3. Chapter 7 (get a book)
4. Quiz
5. Practice
6. Wrap up

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7-1

• Proportions statement equating 2 ratios
• Extreme 3 5 mean
• Mean 5 x extreme
• Pg. 456
• The cross products of proportions are equal
• Product of means equals product of extremes
• Properties of Proportions pg. 458

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Proportions We Do

• Pg. 459 10, 12
• Pg. 460 18, 20
• Pg. 460 28, 30
• You do 7 1 worksheet (1, 5, 7, 8, 10, 12, 14)

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Do Now

• Solve the following proportions
• 1)
• x/4 77/ 281
• 2)
• 8 / (2y 3) 6 / (y 4)

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launch

• About congruence and similarity and triangle thms.

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Proving similar triangles

• 2 triangles are similar if and only if
  corresponding angles are congruent
  corresponding sides are proportional
• Pg. 461 50

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Theorems

• 7 -1 SAS pg. 475
• 7-2 SSS
• Examples pg. 476
• Proof pg. 477

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Algebra review

• Solving quadratic equations pg. 462

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Do now

• Pg. 480 8 9 in book
• Follow directions, use sentences to prove
• When everyone here we are going to media center,
  you dont need to bring anything, except
  pen/pencil

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AA similarity postulate

• Angle angle postulate
• If two angles of one triangle are congruent to
  two angles of another triangle then the triangles
  are similar
• Pg. 474

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10-10-12

• 15 minutes of D.E.A.R
• Warm up on board
• Bring test up when done
• When done get a book, turn to page 515 and read
  about pythagorean thm

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7- 2 similar polygons

• Similar figures have same shape, not necessarily
  same size ( similar)
• Similar polygons pg. 463
• Scale factor ratio of corresponding linear
  measurements of two similar figures

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We do

• Scale drawing and scale pg. 467
• Pg. 469 12, 16
• Pg. 470 22, 24
• Pg. 470 32
• Pg. 471 50, 52, 54

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We do

• Pg. 480 8, 10
• Pg. 481 16
• You do pg. 481 20, pg. 482 26,
• You do pg. 482 38, 40

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Wrap up

• Solve the following proportion
• 3
• X 2 x 1
• Describe corresponding angles of parallel lines
  and how do they compare with corresponding angles
  in polygons

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homework

• Remember, your area/scale factor drawing is due
  Friday
• Test Tuesday 10/9/12