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Sewanhaka High School Math 8 Class:______________ Mrs. Lidowsky, Principal Mr. Long, Teacher Date:________________________ Name:__________________ H.W. #27: Ditto DO-NOW #27: Answer the following questions: 1) Write the equation of a line that 2) Kerriann cut a piece of fabric that passes through the points (-3, 1) and was 7.8 meters long into 12 pieces of (-2, -1) in point-slope form, slopeequal length. What was the length of intercept form and standard form. each piece? Topic: Geometry Main Idea: Similar Polygons Aim: RECALL NOTES Compare the triangles in picture 1. What can you say about them? Compare the polygons in picture 2. What can you say about them? What does it mean for 2 polygons to be similar? What determines the shape of the 2 polygons in picture 2 to be the same? Refer to picture 2. List all of the corresponding angles that are congruent. 3) David works 6.5 hours each weekend at a bakery. What is his hourly wage if he earns $46.80 each weekend? STATEMENT: Here, as in all similar figures, the ratios of the lengths of corresponding sides are equal. Because the ratios are equal, we say that the corresponding sides are in proportion. Two polygons are similar if their corresponding angles are congruent and their corresponding sides are in proportion. This ratio of 2:1 is called the scale factor. It is the ratio of the lengths of the two corresponding sides of the two similar polygons. D C D' C' 12 cm x A B 16 cm A' 8 cm B' Rectangle ABCD is similar to rectangle A'B'C'D', side AB = 16 centimeters, side AD = 12 cm, and A'B' = 8 cm. Find the length of AD . Drill: Answer the following questions. Show work. 1) Is parallelogram ABCD similar to rectangle EFGH? Prove as to why or why not? 2) The two triangles are similar. Find the missing side measures. SUMMARY: If time: Answer the following question. Show work A tree 29¾ feet tall casts a shadow 42 feet long. Mr. Short is 4¼ feet tall. How long is Mr. Short’s shadow? Draw a diagram to represent your work.