# Tangent Circles to Two Parallel Lines and Passing through a Point

Tangent Circles to Two Parallel Lines and Passing through a Point

This Demonstration is based on an example from a Wolfram Education Group seminar: Given two parallel lines and a point between them, draw circles of radius centered at and through and tangent to the lines. Then the circle centered at with radius passes through and .

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Here we allow the two blue circles to be constructed when the point is not between the two lines.