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ABC
Try it on the Geometry BoardUses:Copy a lengthMidpoint and perpendicular bisectorPerpendicular from a pointBisect an angle

Nagel point

Marks where the lines from each corner to an excircle's touch point on the opposite side meet. Ruler and compass only.

All parts
Part 1 of 12: Bisect the angle at AStep 1 of 12Compass

The incentre lies on the line that splits the angle at A in half. Put the point of your compass on the corner, A.

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