Linear Equation Algorithm

/**

 * Class for solving linear equation

 * 

 * @author  : irfanudin ridho

 * @email   : irfan.ub@gmail.com

 * @date    : December 25, 2010

 * @version : 1.0

 */

/**

 * Constructor service.

 * The equation supplied must be in the form:

 * ax+bx+c

 * This class is very limited in the for of the simple equation

 *

 * @param fa string the first linear equation

 * @param fb string the second linear equation

 */

function LinearEquation(fa,fb){
    this.fa = fa;
    this.fb = fb;

    var terma = this.fa.split(/[-+]/g);
    var a1 = terma[0].split(/x/)[0];
    var b1 = terma[1].split(/y/)[0];
    var c1 = terma[2];
    a1 = eval(a1);
    b1 = eval(b1);
    c1 = eval(c1);

    var termb = this.fb.split(/[+-]/g);
    var a2 = termb[0].split(/x/)[0];
    var b2 = termb[1].split(/y/)[0];
    var c2 = termb[2];
    a2 = eval(a2);
    b2 = eval(b2);
    c2 = eval(c2);
  
    this.x = ((b2*c1)-(c2*b1)) / ((a2*b1)-(b2*a1));
    this.y = (-c1 - a1*this.x) / b1;
}

/**

 * method to get the x,y value in array

 * @return array x,y value

 */
LinearEquation.prototype.getXY = function(){
    var data = new Array();
    data[0] = this.x;
    data[1] = this.y;
    return data;
};

/**

 * method to get x value

 * @return number x value

 */
LinearEquation.prototype.getX = function(){
    return this.x;
};

/**

 * method to get y value

 * @return number y value

 */
LinearEquation.prototype.getY = function(){
    return this.y;
};