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AMP 2013-2014: Saturday #2. Ted Coe, Grand Canyon University, 2013. Some materials were also created or refined as part of the development of the “Math 5: Geometry” curriculum for Arizona State University’s Teaching Foundations Project. . My Summary. Ways of doing Ways of thinking
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AMP 2013-2014: Saturday #2 Ted Coe, Grand Canyon University, 2013. Some materials were also created or refined as part of the development of the “Math 5: Geometry” curriculum for Arizona State University’s Teaching Foundations Project.
My Summary • Ways of doing • Ways of thinking • Habits of thinking http://www.youtube.com/watch?v=ZffZvSH285c
The Broomsticks The RED broomstick is three feet long The YELLOW broomstick is four feet long The GREEN broomstick is six feet long
Perimeter What is “it”? Is the perimeter a measurement? …or is “it” something we can measure?
Perimeter • Is perimeter a one-dimensional, two-dimensional, or three-dimensional thing? • Does this room have a perimeter?
Measurement What do we mean when we talk about “measurement”?
How about this? Measurement • Determine the attribute you want to measure • Find something else with the same attribute. Use it as the measuring unit. • Compare the two: multiplicatively.
Draw the following parallel and perpendicular lines: X Z Y Y: Perpendicular to line “X” passing through the corner of the opposite square Z: Perpendicular to line “Y” passing through the intersection of the square and line “Y”. X: Along the right side of the hypotenuse’s square
Draw the following parallel and perpendicular lines: X Z Y Y: Perpendicular to line “X” passing through the corner of the opposite square Z: Perpendicular to line “Y” passing through the intersection of the square and line “Y”. X: Along the right side of the hypotenuse’s square
Area of one green triangle = a b Area of blue square = a c Area of whole (red) square = c b OR This means that: b c c a b a
Find the dimensions of the rectangle • Find the area of the rectangle
Find the dimensions of the rectangle • Find the area of the rectangle • Find a rectangle somewhere in the room similar to the shaded triangle
Or not… http://goldenratiomyth.weebly.com/
Working with similar figures • “Similar means same shape different size.” • “All rectangles are the same shape. They are all rectangles!” • “Therefore all rectangles are similar.”
What is a scale factor? Teaching Geometry According to the Common Core Standards, H. Wu Revised: April 15, 2012. Grade 7 notes, p.49: