Math 8: similarity
Notes #45
Section #5: Angle-Angle Criterion for Similar Triangles 8.G.5.
Corresponds with Module 3, Lessons 10.
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Example#1: Are the triangles below similar? Present an informal argument as to why
they are or why they are not.
Using a protractor, what can you say about the angle measures of the triangles?
Key Concept!
Similar Triangles are triangles that have the same ____________, but not necessarily
the same ______________.
 The shape of a triangle is determined by its __________________.
o So if two triangles have the same shape, then their corresponding angles are
congruent.
Example #2: Are the following triangles similar? Explain your reasoning.
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 The Angle-Angle similarity theorem (AA) says that if at least two angles in one
triangle are congruent to two angles in another triangle, then the triangles are similar.
Practice: Are the triangles shown below similar? Present an informal argument as to
why they are or why they are not.
Math 8: similarity
HW #45
Section #5: Angle-Angle Criterion for Similar Triangles 8.G.5.
Corresponds with Module 3, Lessons 10.
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1.
Are the triangles shown below similar? Present an informal argument as to why they are or why they are not.
2.
Are the triangles shown below similar? Present an informal argument as to why they are or why they are not.
3.
Are the triangles shown below similar? Present an informal argument as to why they are or why they are not.
MORE ON BACK!!!!!
4.
Are the triangles shown below similar? Present an informal argument as to why they are or why they are not.
5.
Are the triangles shown below similar? Present an informal argument as to why they are or why they are not.
6.
Are the triangles shown below similar? Present an informal argument as to why they are or why they are not.
7.
The diagram shows a pair of similar triangles. Find the value of x.