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Re: inscribing a circle
Posted:
Dec 20, 1999 9:51 PM


Hi Hakan,
I think that you need to _construct_ the circle after you find its centre rather than _draw_ it . To do this, (1) draw a line through the center (intersection of the angle bisectors) which is perpendicular to one of the sides of the triangle. (2) construct a point at the intersection of the perpendicular and the side (3) construct a circle with center point at the angle bisectors' intersection and as the radius point use the point constructed in (2). This should give you the incircle, which touches the triangle at 3 points.
Regards,
Jon Roberts
Hakan Aras wrote:
> When I draw an inscribed circle in any triangle using the intersection point > of the angle bisectors as the center point of that circle, Cabri and > Sketchpad claim that they have no intersection point(s) although visually > the circle seems to touch the triangle at three points. When I enlarge the > circle a little, this time those sofware claim that it touches the triangle > at six points( two intersection points for each vertex).There is no other > case between these.As far as i know from my experiences. > But theoretically every inscribed circle is drawn by using the intersection > point of the angle bisectors as the center point of that circle. > So does it mean that these software are deficient to do this task?



