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Tangent1Detailed.d9019ee701e5626fd6a49abcb3bd57b0.png

Instruction: Construct a tangent to the circle at the given point.

Goal: 2L 3E

Available tools:

  • Move
  • Point
  • Line
  • Circle
  • Perpendicular Bisector
  • Perpendicular
  • Angle Bisector
  • Intersect

Pack: Beta

Previous level: 2.7

Next level: 2.9

2L solution[]

Let O be the center of the circle and A the point on it.

  1. Construct line OA
  2. Construct the perpendicular to the line OA from point A

3E solution[]

2-8 Tangent to Circle at Point 3E.jpg

Let O be the center of the circle and A the point on it.

  1. Construct a circle with an arbitrary center B on the circle and radius AB, intersecting circle O at C
  2. Construct the circle with center A and radius AC, intersecting circle B at D
  3. Construct line AD

Explanation[]

Solution 2L is easy as a tangent is simply a line perpendicular to a radius at a point on the circle.


Solution 3E is an application of Thales

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