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Perpendicular Construction Selector

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About This MicroSim

This interactive tool demonstrates both methods for constructing perpendicular lines using compass and straightedge. Switch between modes to learn when to use each method.

Two Construction Methods

Point ON Line

Step Action
1 Draw arcs from P on both sides, mark A and B
2 Draw arc from A above the line
3 Draw arc from B (same radius) to intersect
4 Mark intersection point Q
5 Draw line PQ - perpendicular through P

Point NOT on Line

Step Action
1 Draw arc from P crossing line at A and B
2 Draw arc from A on opposite side of P
3 Draw arc from B (same radius) to intersect
4 Mark intersection point Q
5 Draw line PQ - perpendicular to ℓ

How to Use

  1. Select mode: Choose "Point ON Line" or "Point NOT on Line"
  2. Step through: Use Next/Prev buttons or Auto play
  3. Compare methods: Notice the different arc placements

Learning Objectives

  • Choose the correct perpendicular construction based on point position
  • Execute both perpendicular construction methods
  • Analyze why each method works geometrically

Bloom's Taxonomy Level

Applying, Analyzing, and Evaluating - Method selection and execution.

Iframe Embed Code

<iframe src="https://dmccreary.github.io/geometry-course/sims/perpendicular-construction-selector/main.html"
        height="602px"
        width="100%"
        scrolling="no"></iframe>