I have a circle. I know 2 points that are in the circunference. I also know one line that touches the center. How can I calculate the center?

Question

osanseviero · Answer

What I thought would be: Getting the equation of the line of the two points, then the perpendicular, then saying it is equal to the other line.

anonymous · Answer

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find slope of line AB,m=(y2-y1)/(x2-x1)
slope of line PD=-1/m=M
find mid-point L and eq. of line through L by y-y3=M(x-x3)
find the point of intersection of this line PD with the given line say MN.
it is centre.

osanseviero · Answer

I forgot about midpoing D: D: D: