Geometry / Mr. Hansen 11/5/2004

Name: _______________________

Brain Teasers Created by Students

1.

Andrew M.

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F

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J

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B

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	Does the letter Z belong above or below the line? What is the rule?
2.	Nick T. (edited by Mr. Hansen)
	For parts 1-3, it is very helpful to know that a radius is perpendicular to a tangent line when the two intersect at the point of tangency. This is given as a postulate on p. 459 of the Rhoad/Milauskas/Whipple textbook, Geometry for Enjoyment and Challenge. Part 4 requires trigonometry and some clever work. It is remarkable that the angle is uniquely determined simply by the conditions of tangency and having EC = ID; it is also remarkable that the angle is approximately 32°32'3.2''.