You are given a white sheet, a ruler without any graduation, and a compass. Drawn on the sheet are a circle its center and a point on the circle. Since you can only draw circles and straight lines, what is the fewest number of circles and/or straight lines you have to draw in order to have drawn the tangent line of the circle that passes through the point
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First draw an arbitrary red circle with center on the circumference of black circle and passing through point A . Then draw blue circle, and then draw purple tangent.
The dashed line and circle shows the symmetry