AIM: How can we use similar triangles to measure tall objects?
HW: ACE# 15-16, p.94
Classwork: As we learned in class today, people have been using similar triangles to measure tall objects and structures for a looooooong time. In fact, a Greek mathematician once used shadows formed by the Great Pyramids of Giza to calculate its height, all without even climbing to the top. He realized that when the rays of the sun hit different objects, their shadows form similar triangles. If he could measure the length of the shadows on the ground, and measure the height of a much shorter object, he would have enough information to find the height of the pyramids (by using proportions or scale factors.)
Use this concept to answer questions from your homework. Remember to draw pictures to model the situations from the word problems. Label the diagrams with the given information and then determine scale factors or set up a proportion to find missing heights.