The program prompts for 3 circles' center coordinates and their radii.
The program then prompts for a point which is then evaluated for inclusion/exclusion in the three circles' areas.

Code:
#include <iostream>
#include <cmath>
using namespace std;

int main()
{
  // Variable declarations
  double x1;                 // x coordinate circle A
  double y1;                 // y coordinate circle A
  double x2;                 // x coordinate circle B
  double y2;                 // y coordinate circle B
  double x3;                 // x coordinate circle C
  double y3;                 // y coordinate circle B
  double r1;                 // radii circle A
  double r2;                 // radii circle B
  double r3;                 // radii circle C
  double X;                  // query x coordinate
  double Y;                  // query y coordinate
  double dx1 = X - x1;         // x distance between query and circle A
  double dy1 = Y - y1;         // y distance between query and circle A
  double dx2 = X - x2;         // x distance between query and circle B
  double dy2 = Y - y2;         // y distance between query and circle B
  double dx3 = X - x3;         // x distance between query and circle C
  double dy3 = Y - y3;         // y distance between query and circle C
  bool c1;                   // query point in circle A y/n
  bool c2;                   // query point in circle B y/n
  bool c3;                   // query point in circle C y/n

  // Prompt and read in circle A center coordinates
  cout << "Enter x and y coordinates of circle A (2 values): ";
  cin >> x1;
  cin >> y1;

  // Prompt and read in circle A radius
  cout << "Enter radius of circle A: ";
  cin >> r1;

  // Prompt and read in circle B center coordinates
  cout << "Enter x and y coordinates of circle B (2 values): ";
  cin >> x2;
  cin >> y2;

  // Prompt and read in circle B radius
  cout << "Enter radius of circle B: ";
  cin >> r2;

  // Prompt and read in circle C center coordinates
  cout << "Enter x and y coordinates of circle C (2 values): ";
  cin >> x3;
  cin >> y3;

  // Prompt and read in circle C radius
  cout << "Enter radius of circle C: ";
  cin >> r3;

  // Prompt and read in query point
  cout << "Enter x and y coordinates of query point (2 values): ";
  cin >> X;
  cin >> Y;

  // Determine location of query point relative to the circles  
  if ((dx1*dx1)+(dy1*dy1) <= (r1*r1)) { 
      c1 = 1;
  }
    else {
      c1 = 0;
    }
  if ((dx2*dx2)+(dy2*dy2) <= (r2*r2)) {
      c2 = 1;
  }
    else {
      c2 = 0;
    }
  if ((dx3*dx3)+(dy3*dy3) <= (r3*r3)) {
      c3 = 1;
  }
    else {
      c3 = 0;
    }

  // Determine whether circles contain query point
  if (c1 == 0 && c2 == 0 && c3 == 0) {
      cout << "No circle contains point (" << X << "," << Y << ")." ;
    }
  else if (c1 == 1 && c2 == 0 && c3 == 0) {
      cout << "Circle A contains point (" << X << "," << Y << ")." ;
    }
  else if (c1 == 0 && c2 == 1 && c3 == 0) {
      cout << "Circle B contains point (" << X << "," << Y << ")." ;
    }
  else if (c1 == 0 && c2 == 0 && c3 == 1) {
      cout << "Circle C contains point (" << X << "," << Y << ")." ;
    }
  else if (c1 == 1 && c2 == 1 && c3 == 0) {
      cout << "Circles A and B contain point (" << X << "," << Y << ")." ;
    }
  else if (c1 == 1 && c2 == 0 && c3 == 1) {
      cout << "Circles A and C contain point (" << X << "," << Y << ")." ;
    }
  else if (c1 == 0 && c2 == 1 && c3 == 1) {
      cout << "Circles B and C contain point (" << X << "," << Y << ")." ;
    }
  else cout << "Circles A, B and C contain point (" << X << "," << Y << ")." ;
}
For circles A(0,0) r=5, B(0,0) r=5, C(0,0) r=5, Point (-10,-10), I somehow get the output "Circles A, B, and C contain point (-10,-10). This happens for all values I have tried, whether it is a valid output statement or not. What am I doing wrong?