using System;

public class Program

{

    public static void Main()

    {

        int x1 = 2;

        int x2 = 5;

​

        float y1 = 7.5f;

        float y2 = 12f;

        for (float i = -999; i < 999; i+=0.5f)

        {

            if ((y1 - i) / x1 == (y2 - i) / x2)

            {

                Console.WriteLine("y=" + (y1 - i) / 2 + "x+" + i);

​

                break;

            }

        }

    }

}