Download Saccheri Quadrilaterals in Neutral Geometry E D A C B

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts

Line (geometry) wikipedia , lookup

Rational trigonometry wikipedia , lookup

Multilateration wikipedia , lookup

History of trigonometry wikipedia , lookup

Trigonometric functions wikipedia , lookup

History of geometry wikipedia , lookup

Euler angles wikipedia , lookup

Euclidean geometry wikipedia , lookup

Transcript
Saccheri Quadrilaterals in Neutral Geometry
€
A Saccheri Quadrilateral is a quadrilateral with congruent opposite sides that are both
perpendicular to the base. Quad ABCD is a Saccheri Quadrilatreal. We call BC the base,
AD the summit, and angles ∠BAD and ∠CDA the summit angles.
A
D
€
€
€
B
C
First, show the following two results in neutral (absolute) geometry:
1. The diagonals of a Saccheri Quadrilateral are congruent.
2. The summit angles of a Saccheri Quadrilateral are congruent.
Here are several more results related to Saccheri Quadrilaterals. Try to come up with a
way to justify each of the following results:
3. The line joining the midpoints of the summit and base of a Saccheri Quadrilateral
is perpendicular to both the summit and base.
4. The angle sum of a triangle ( ΔAED ) is equal to the sum of the summit angles of
its associated Saccheri Quadrilateral.
A
D
€
B
C
E
5. The summit angles of a Saccheri Quadrilateral are each less than or equal to 90
degrees. (Hint: Use the result from #4 above.)