Question 719099
Show that the points 3+2i,2-i,1+i,4+i lies on a circle. Find its center and radius.
================
Plot the points on the x-y plane, A(3,2), B(2,-1), C(1,1) & D(4,1)
Check that no 3 of the points are colinear by finding the slopes of
DA, AB, BC & CD (going in order of xes)
-----
Any 3 non-colinear points define a circle.
Get the equations of the perpendicular bisectors of 2 lines, AB & BC will do.
The intersection of the bisectors is the center of the circle.
The distance from the center to any of the A, B or C is the radius.
----------
Check that point D is on the circle.