Download Geometry 6.3 Similar Polygons Notes

Geometry 6.3 Similar Polygons Notes
Big Idea:
February 10, 2016
Agenda:
What are similar polygons?
What is the least amount of information
needed to prove that triangles are similar?
-You will evaluate the lengths of sides and measures
of angles by applying the definition of similar polygons
- You will compare the ratio of corresponding sides of
similar polygons to the ratio of their perimeters.
­ Foldable ­ Similar Polygons
­ Practice with similar polygons
­ Proving triangles similar
­ HW #6.3/6.4 1
Geometry 6.3 Similar Polygons Notes
February 10, 2016
2/10 Warm-Up
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2.
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
How do the angles compare?
How do the sides compare?
B
Q
R
C
P
A
These are similar triangles
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
B
Q
C
R
P
A
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
Let's make a foldable...
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
Determine whether the following pairs of polygons are similar. If they are similar, write a similarity statement.
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
p. 109 in practice workbook
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
1) Find a scale factor
2) Write a proportion ­ match up like things 3) Solve the proportion
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
Please complete the following problems in your PW on p.110.
­ What is perimeter?
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
If triangles are similar, all corresponding segments have the
same ratio.
These are altitudes
These are medians
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Geometry 6.3 Similar Polygons Notes
February 10, 2016
One paper per person - only one paper will be evaluated.
1. Find the values of x and y.
2. Find the perimeters of the two triangles.
3. Find the areas of the two triangles.
4. Find the ratio
5. Find the ratios of the perimeters and the ratios of the areas. How do these compare to the ratio in #4? 12
Geometry 6.3 Similar Polygons Notes
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#6.3 (PW)p.109­111: 3­22
February 10, 2016
Similar Polygons
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