#include #include using namespace std;

// a structure to represent a point in 2D , the x and y co-ordinates class Point { double x; double y; public: Point() //default constructor initiializing to (0,0) { x=y=0; } Point(double x1,double y1) { x=x1; y=y1; } double getX() { return x; } double getY() { return y; } void display() { cout<<"("< } }; /*class representing circle with center (a,b) and radius r*/ class Circle { Point center; double radius; public: Circle(Point cent,double rad) { center=cent; radius=rad; } void setCenter(double x,double y) { center=Point(x,y); } void setRadius(double r) { radius=r; } //display the circle equation void displayCircleEq() { cout<<" (x-"<

//class representing a line with equation y=mx+c class Line { double m; double c; public: Line(int m1,int c1) { m=m1; c=c1; } double getM() { return m; } double getC() { return c; } void display() { cout<<" line y= "<

Point * calculateIntersection(Circle &cir,Line& lin) { double A,B,C; double m=lin.getM(),c=lin.getC(),a=cir.getCenter().getX(),b=cir.getCenter().getY(); double r=cir.getRadius(); double x1,y1,x2,y2, d; A=pow(m,2)+1; // A=m^2 + 1 B=2*(m*c-m*b-a); //B=2(mc-mb-a) C= pow(a,2)+pow(b,2)-pow(r,2)+pow(c,2)-2*b*c;//a^2+b^2-r^2+c^2-2bc d=sqrt(pow(B,2)-4*A*C); //calculate sqrt(B^2-4AC) //first root x=(-B+sqrt(B^2-4AC)) / 2A x1=(-B+d)/(2*A); //second root x=(-B-sqrt(B^2-4AC)) / 2A x2=(-B+d)/(2*A); //using line equation to get y values y1=m*x1+c; y2=m*x2+c; Point *intersection=new Point[2]; intersection[0] =Point(x1,y1); intersection[1] =Point(x2,y2); //the 2 intersection points stored in array and returned return intersection; }

int main() {

Circle circle(Point(0,0),5); //circle with origin as center and radius 5 Line line(1,0); // line y=x Point *inter=calculateIntersection(circle,line); circle.display(); circle.displayCircleEq(); line.display(); cout<<" intersection points are "; cout<<" Point 1: "; inter[0].display(); cout<<" Point 2: "; inter[1].display(); return 0; }

*************************** we have not covered pointers to objects for classes yet/ revise without the use of the pointers to objects c++ / this needs to be simplified /cin input center and radius thanks c++ this should be a basic class program to determine intersection points for a straight line through a circle