5.3+Using+Similar+Triangles+to+find+Distances

6.11.08 MT Block E __Essential Question #4/5 -__ What types of situations can I use my similarity ideas to solve? __Big idea:__ Many things in our world are mathematically similar and we can use this to understand and describe the world around us

Notes from Class:
Simiar triangls have corresponding angles and sides. =__5.3 Using Similar Triangles to Find Distances__=

//Mr.Anwar's class went to Bevort Pond for a picnic. Darnell, Angie, and Trevor wanted to find the distance across the pond. Darnell and Angie suggested that Trevor swim across with the end of a tape measure in his mouth. Trevor declined- the water was very cold! They decide to try to use what they had learned about similar triangles to finf the distance across the pond. They drew a diagram and started making the necessary measurements.//

Here is the diagram Darnell, Angie and Trevor made, including their measurments. A. Name the two similar triangles in the diagram.** ADE and ABC are the two similar triangles.
 * __Problem 5.3__

The scale factor is 0.75. __Calculations__ 120/160=0.75 To find the scale factor you divide the small triangle's measurements by the large triangle's measurements. The distance is 52.5ft. __Calculations__ 70x0.75=52.5ft To find the distance across the pond you times the scale factor by the corresponding side of the large triangle which in this case is 70ft.
 * B. What is the scale factor from the large triangle to the small triangle?**
 * C.What is the distance across the pond(measured along the dotted line)?**

We were not required to do this.
 * D. On your school grounds or in your neighbor hood, find a pond or some other feature such as a park, a playground, or a wooden area. Use the ideas in the problem to estimate the distance across the feature. Explain you work carefully.**

Is the large triangle Darnell, Angie, and Trevor measured the only one that will work to find the distance across the pond? If you think other triangles could be used, make a drawing of Bevort pond showing another triangle that could be measured to determine the distance across the pond. If you think no other triangles would work, explain why not.** No, you can do it with other triangles as long as there bases are parallel. Here is another way you can use a triangle to measure Bevort pond:
 * __Problem 5.3 Follow-Up__