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ABC
Try it on the Geometry BoardUses:Perpendicular from a point

Altitude

Draws the line from a corner of a triangle at right angles to the opposite side. Ruler and compass only.

Part 1 of 1: Perpendicular from the vertex to the opposite sideStep 1 of 12Compass

The altitude from C meets AB at a right angle (extend AB if you need to). Put the point of your compass on C.

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