Archive for the ‘Math Notes’ Category

Finding the Circle Through Three Points

November 4, 2011 Leave a comment

I have decided to occasionally write some notes on this blog.

You must first find the perpendicular bisectors (a perpendicular line at the midpoint between two points) for both lines (“AB” and “BC” in this case). Where these two perpendicular bisectors intersect is the centre point of the circle (labelled “D” in this case).

Note: The equation to find the midpoint of a line is:
(\frac{1}{2}(x_1+x_2) , \frac{1}{2}(y_1+y_2)) or (\frac{x_1+x_2}{2} , \frac{y_1+y_2}{2})