5.1+Using+Shadows+to+Find+Heights+2011

**JYR** **Math 7H** **Big Idea:** //Many things in our world are mathematically similar and we can use this to understand and describe the world around us. //
 * March 23rd 2011**


 * Essential Question: ** What types situations can I use my similarity ideas to solve?

Notes:
 * I know that when you do the shadow method and there are two triangles. I know that the angles are the same.
 * To find the height of the object, I can measure the lengths of the two shadows and the height of a meterstick or a yardstick and do a crossmultiplication and find the missing height,


 * Mr. Anwar's class is using the shadow method to estimate the height of their school building. They have made the following measurements and sketch.**


 * Length of the meterstick: 1m**
 * Length of the meterstick's shadow: 0.2m**
 * Length of the building's shadow: 7m**



First I would put these informations in proportion so it's like = x/building's shadw X Meterstick/Shadow of Meterstick which will be x/7m X 1m/0.2m. i will do the crossmultiplication and get 7 x 1 and divide it by 0.2 which is 35. So the building is 35meters tall.
 * A. Use what you know about similar triangles to find the building's height from the given measurements. Explain your work.**

My group went to the tennis pole and very pretty tall. We found the shadow of the pole which was 5.2m, Meterstick = 1m and the shadow of the meterstick which was 1.35m. If you put in the proportion it will be Pole height/Shadow of pole X Meterstick/Shadow of Meterstick. Which will be x/5.2m X 1m/1.35m **.** Then I would use the crossmultiplication which is 5.2 X 1 and divide it by 1.35 to find out the height of the pole. It was 3.85... So the height of the pole is **__3.85__**m tall.
 * B. With your class, choose a building or other tall object. Work with your group to estimate the object's height using the shadow method. in your answer, include the measurements your group made, and explain in words and drawings how you used these measurements to find the object. **

We couldn't make a lineplot because we did not choose the same place to use this method so I didn't do it,
 * Problem 5.1 Follow-Up **

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