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AB
Try it on the Geometry BoardUses:Perpendicular at a point

Square on a segment

Builds a square on a segment, with its corners and sides. Ruler and compass only.

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Part 1 of 6: Perpendicular at A (1 of 2)Step 1 of 7Compass

The sides at A and B are at right angles to AB. Put the point of your compass on A.

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