import java.util.Scanner;
public class E325 {
    public static void main(String[] args) {
    /*
     * The purpose of this program is to find the intersect
     * of two lines given by the user by four points
     *
     * Get the four points. x1,y1 x2,y2 x3,y3 x4,y4
     */
    Scanner input = new Scanner(System.in);
    System.out.print("Enter x1 y1, x2 y2, x3 y3, x4 y4: ");
    double x1 = input.nextDouble();
    double y1 = input.nextDouble();
    double x2 = input.nextDouble();
    double y2 = input.nextDouble();
    double x3 = input.nextDouble();
    double y3 = input.nextDouble();
    double x4 = input.nextDouble();
    double y4 = input.nextDouble();

    }
}

y = m*x + b

-m1*x + y = b1
-m2*x + y = b2

[ -m1    1 ]{x} = {b1}
[ -m2    1 ]{y}   {b2}