Writing Equations of Circles

Circles

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Equation of a Circle

Example

Points of Intersection of a Circle & a straight line (y = mx+c)

1. If the line intersects the circle at only 1 point it is a tangent to the circle.

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2. If the line intersects at 2 points and does not go through the center of the circle, it is a secant of the circle.

EG1

EG2