Welcome to class. Please pick up a warm up off the table

1. Welcome to class. Please pick up a warm up off the table and do it!

3. Let’s grade homework Pg 138 – 143; 5-9, 17-21, not 8c

4. 3.1.3 - Proportional Equations3.1.4 – Using Proportional equations

5. A comparison of 2 things. Can be written like: Dogs : cats (in words) 2:1 (with a colon) 3 (as a fraction) 4 An equation where 2 ratios are equal to each other Written like: (3 + x) = 5 7 2 Use cross products to solve. Ratio Proportion

6. How are ratios and proportions the same? How are they different?

7. I will number each row. • Back person: please get the appropriate paper from the back table – one paper for each person – and hand them out. • Second person from the back: please get a straightedge for everyone in your row. • Everyone: please follow the instructions on the paper and complete your paper independently. • In 5 minutes, you will be able to compare your answers to others in your row to come up with a final solution. • Then, make a table and come up with some conjectures..

8. Put a point of dilation somewhere inside the shape. • Measure the sides of your shape in cm. • Dilate the shape by a scale factor of 2. • Find the perimeter of the pre-image. • Find the perimeter of the image. • Find the area of the pre-image. • Find the area of the image. #2 #1 #4 #5 #3

10. D I H E J P C A K B Naming & Comparing Polygons • List vertices in order, either clockwise or counterclockwise. • When comparing 2 polygons, begin at corresponding vertices; name the vertices in order and; go in the same direction. • By doing this you can identify corresponding parts. DCBAE  D corresponds to I AE corresponds to PH IJKPH

11. D 5 5 I H E DC corresponds to IJ CB corresponds to JK BA corresponds to KP AE corresponds to PH ED corresponds to HI How many corresponding angles are there? How many corresponding sides are there? J P C A K B Name corresponding parts • Name all the angles that correspond: D corresponds to  I  C corresponds to  J  B corresponds to  K  A corresponds to  P  E corresponds to  H DCBAE IJKPH • Name all the segments that correspond:

12. 10 D E C A B • How many ways can you name pentagon DCBAE? Do it. Pick a vertex and go clockwise Pick a vertex and go counterclockwise DEABC CDEAB BCDEA ABCDE EABCD DCBAE CBAED BAEDC AEDCB EDCBA

13. A B E F D H C G SIMILARITY STATEMENTS SIMILARITY STATEMENT Similarity Statements • Given: These polygons are similar. • Remember, if they are SIMILAR, corresponding sides have the same RATIO. AB ~ EF DA ~ HE DC ~ HG CB ~ GF ABCD ~ EFGH

14. What about the angles? Corresponding angles in a similar figure are congruent!! What?

15. A B E F D H C G ~ ~ ~ ~ = = = = Corresponding angles in a similar figure are congruent A E B F D H C G

16. Quick check How many different ways can you name ΔABC? What is the relationship of corresponding sides in a similar figure? What is the relationship of corresponding angles in a similar figure? What happens to the perimeter of a shape that has been dilated by a scale factor of 2? What happens to the area of a shape that has been dilated by a scale factor of 2? What is the simplified, exact answer to: √3 + 5√3 ? What is the name of angle pair c and h? Are angles c and hcongruent, supplementary or neither? Defend your answer. What is the name of angle pair b and g? What is the measurement relationship between b and g? Defend your answer. What is the sum of the angles in a triangle? What is the sum of the angles in a quadrilateral? If a shape has a scale factor of 3, is the pre-image larger or smaller than the image?

17. e f a c h g b d

18. Your assignment Pg 146 – 151; 27-31, 38-42