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Learning Math Home
Patterns, Functions, and Algebra
Session 1 Part A Part B Part C Part D Homework
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Session 1 Materials:

Session 1:

Problem H1


Draw five quadrilaterals, each on its own piece of patty paper. Use one quadrilateral for each construction below.


Construct the eight medians of the first quadrilateral. (There will be two medians at each vertex.)


Construct the four midlines of the second quadrilateral.


Construct the four angle bisectors of the third quadrilateral.


Construct the four perpendicular bisectors of the sides of the fourth quadrilateral.


Construct four altitudes in the fifth quadrilateral -- one from each vertex.


Problem H2


Try Problem H1 with a few different quadrilaterals. Don't just use "special" cases, like squares and rectangles. Record any observations about the constructions above. How is the situation different from what you saw with triangles?


Problem H3


Imagine a square casting a shadow on a flat floor or wall. Can the shadow be non-square? Non-rectangular? That is, can the angles in the shadow ever vary from 90°?

Take it Further

Problem H4


Which of these shapes could cast a square shadow, and which could not? Explain how you decided.


Suggested Reading:

Education Development Center, Inc. (2000). Perspective: What Is Geometry? In Connected Geometry: A Habits of Mind Approach to Geometry. Glencoe/McGraw-Hill.
Reproduced with permission from the publisher. Copyright © 2000 by Glencoe/McGraw-Hill. All rights reserved.

Download PDF File:
Perspective: What Is Geometry?


Problems H3 and H4 taken from Connected Geometry, developed by Educational Development Center, Inc. pp. 12-13. © 2000 Glencoe/McGraw-Hill. Used with permission. www.glencoe.com/sec/math

Next > Session 2: Triangles and Quadrilaterals

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