Take out your 11.1 Worksheet ready to be stamped. Take out a compass and protractor. What does it mean for polygons to be similar? Give a counterexample.

Take out your 11.1 Worksheet ready to be stamped.

Take out a compass and protractor. What does it mean for polygons to be similar?

Give a counterexample to each statement. (Can be in the form of a picture or explanation.)◦ Two polygons that have corresponding angles congruent must be similar.

◦ Two polygons that have corresponding sides proportional must be similar.

11.2 WS is due Wednesday Parts 1-2 of the house project are due Wednesday

Bring your raffle tickets for an auction on Wednesday

Bring your compasses every day next week

Discover shortcut methods for determining similar triangles

Use proportions to find measures in similar figures

Use problem solving skills

We concluded that you must know about both the angles and the sides of two polygons in order to make a valid conclusion about their similarity.

However, triangles are unique. Remember there were 4 shortcuts for triangle congruence: SSS, SAS, ASA, and SAA.

Are there shortcuts for similarity also?

Suppose two triangles had one corresponding angle congruent. Would the triangles be similar?

From the second step in the investigation you see there is no need to check AAA, ASA, or SAA similarity conjectures.

Because of the Triangle Sum Conjecture and the Third Angle Conjecture AA Similarity Conjecture is all you need.

So SSS, AAA, ASA and SAA are shortcuts for triangle similarity.

Discover shortcut methods for determining similar triangles

Use proportions to find measures in similar figures

Use problem solving skills

1. Find the missing values.Show your work andExplain your reasoning

2. Write the similarity statement and give a proof of why the triangles are similar.

1. Find the missing values.Show your work andExplain your reasoning

2. Write the similarity statement and give a proof of why the triangles are similar.