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Interesting Circle Geometry question. Who can answer it?
Picture an angle inside a circle with the vertex as a point on the edge of the circle. The angle is a line that goes thru the center of the center.
Prove why the line that connects the two end points of the angle is perpendicularly bisected by the diameter or radius.
3 Answers
- Rita the dogLv 78 years agoFavorite Answer
I think you want to prove that every angle inscribed in a semi-circle is a right angle. More generally, every angle inscribed in a circle equals 1/2 the central angle that subtends the same arc. This is proved in elementary geometry and depends only on the fact that the exterior angle of any triangle is the sum of the opposite two interior angles.
- 8 years ago
Because it's a tangent. Difficult to explain without diagrams, so take a look at http://en.wikipedia.org/wiki/Tangent_lines_to_circ...
