Find m right angle R .
(12r + 3)
(7x- 13)

Denote the points wherein Lisa, Bree, and Caleb are by L, B and C.
Suppose that the three points are not linear. Otherwise the equidistant 
point is on the line that goes through L, B and C. 
We can think different aspect of the equidistance point E. 
Since EL=EB=EC, then E is the centre of the circle that passes through 
the points LBC.
Furthermore, if we draw the three circles with centers L, B and C, then 
those circle will intersect in only one point P if 
P is the equidistance point E. 
So there is two geometric constructions with circles.