Circle circa;
Circle circb;
Circle circc;
boolean mouseDown = false;
void setup(){
 size(300,300);
 smooth();
 circa = new Circle(75,150,75);
 circb = new Circle(225,150,75);
 circc = new Circle(150,75,50);
 solve(circa,circb,circc);
}

void draw(){
  background(120);
  if(mouseDown){
    if(mouseX > 150){
      circb.cenx++;
    } else {
     circb.cenx--; 
    }
    solve(circa,circb,circc); 
  }
  circa.drawme();
  circb.drawme();
  circc.drawme();
}

void mousePressed(){
 mouseDown = true;
}

void mouseReleased(){
 mouseDown = false;
}

void solve(Circle a, Circle b, Circle c){
  float d = sqrt((a.cenx-b.cenx)*(a.cenx-b.cenx)+(a.ceny-b.ceny)*(a.ceny-b.ceny));
  println(d);
  float arad = a.rad+c.rad;
  float brad = b.rad+c.rad;
  float nx = (d*d - arad*arad + brad*brad)/(2*d);
  println(a.cenx+nx);
  float ny = sqrt((4*d*d*brad*brad - (d*d - arad*arad + brad*brad)*(d*d - arad*arad + brad*brad))/(4*d*d));
  println(ny);
  c.cenx = a.cenx+nx;
  c.ceny = a.ceny-ny;
}