1. Lesson 1.2 Proportions as Models

2. How many inches are in 7.5 feet? Set up and use a proportion to solve. What do you know?1 foot = 12 inches Not correct—note the labels don’t match 7.5(12) = 1x 90 inches = x How else might you set up this proportion?

3. According to the American Automobile Association (AAA), the overall cost of owning and operating a passenger vehicle averages $7,834 based on 15,000 miles of driving. If the cost per mile is constant, about what would it cost to drive 12,000 miles? Let c represent the cost of driving 12,000 miles. Write a proportion for the problem. Avg cost # of miles Two options 7,834(12,000) = 15,000c 94,008,000= 15,000c 6,267.20 = c

4. Similar —two figures that have the same shape, but not necessarily the same size. Similar polygons —corresponding angels are equal in measure and the Lengths of corresponding sides are proportional. Scale factor: if 2 polygons are similar then the ratio of the lengths of 2 corresponding sides is called the scale factor. What is the scale factor of ABCD to KLMN? Given: ABCD ~ KLMN What is the value of x? 4x = 5(6) 4x = 30 x = 7.5

5. Assignment: page 9-10: 1-11