PPT-ALGEBRA I @ SECTION 2-8 : PROPORTIONS and SIMILAR FIGURES

1 A sailboat and its model are shown at the right What is the length of the model sailboat 18 feet 25 feet 10 f t ANSWER 72 feet SIMILAR FIGURES have the same shape though not necessarily the same size . What are similar polygons?. Two polygons are similar if corresponding (matching) angles are congruent and the lengths of corresponding sides are proportional.. Congruent Figures. In order to be congruent, two figures must be the same size and same shape.. Objectives. Learn to . write and solve problems using proportions. . Proportions. Proportions are frequently used to solve problems in mathematics.. Proportional reasoning can be applied in many situations, including reading and drawing maps, architecture, and construction. . . Pythagoras (560-480 BC), the Greek geometer, was especially interested in the golden section, and proved that it was the basis for the proportions of the human figure. He showed that the human body is built with each part in a definite golden proportion to all the other parts.. Proportions. What are proportions?. - If two ratios are equal, they form a proportion. Proportions can be used in geometry when working with similar figures.. What do we mean by similar?. - Similar describes things which have the same shape but are not the same size.. What are similar polygons?. Two polygons are similar if corresponding (matching) angles are congruent and the lengths of corresponding sides are proportional.. Congruent Figures. In order to be congruent, two figures must be the same size and same shape.. (Not exactly the same, but pretty close!). A dilation is when you create a similar figure that is . larger or smaller . than the original figure. Each side is multiplied by the same scale factor, so the new dilated shape is proportional to the original.. Statistics. What you will learn. Be able to state the null and alternative hypotheses for testing the difference between two population proportions.. Know how to examine your data for violations of conditions that would make inference about the difference between the two population proportions unwise or invalid.. Introduction. This chapter focuses on basic manipulation of Algebra. It also goes over rules of Surds and Indices. It is essential that you understand this whole chapter as it links into most of the others!. Section 2-8. Goals. Goal. To find missing lengths in similar figures.. To use similar figures when measuring indirectly.. Rubric. Level 1 – Know the goals.. Level 2 – Fully understand the goals.. Lesson 5.2: Proportions. Chapter Five: Ratios and Proportions. Lesson 5.2: Proportions. Chapter Five: Ratios and Proportions. Lesson 5.2: Proportions. Chapter Five: Ratios and Proportions. Lesson 5.2: Proportions. Difference Between Proportions. Sometimes we want to see if there is a significant difference between independent groups.. Control group vs. treatment group or placebo group. Men vs. women. Last year vs. this year. 1) A sailboat and its model are shown at the right. What is the length of the model sailboat?. 18 feet. 25 feet. ??. 10. f. t.. ANSWER : 7.2 feet. SIMILAR FIGURES :. . have the same shape, though not necessarily the same size. . Proportion – Learning Outcomes Express quantities as proportions of each other using fractions, decimals, ratios, and percentages. Divide quantities into a given proportion. Express errors as a proportion. Proportions and Similar Figures What is Similarity? Not Similar Similar Similar Not Similar Similar Triangles Similar Figures Figures that have the same shape but not necessarily the same size are