Acute Angle result

In assuming the angles of the Saccheri quad to be less than Pi, Saccheri was able to show the following result of hyperbolic space.

There exits a line, perpendicular to one arm of an acute angle that does not meet the other. He then showed that the sum of the angles of a triangle is less than Pi. Move the point M along the one arm of the angle to show this result.

However he went on to claim a (false) result that showed it was impossible for his assumption to hold and hence that hyperbolic geometry could not exist.

Saccheri Quadrilateral Poincaré Bug

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