public function getAbscissaByOrdinate($y)
    {
        if ($this->isVertical()) {
            return $this->getPointA()->getAbscissa();
        }
        return (($y - $this->getYIntercept()) / $this->getSlope());
    }
public function getAbscissaByOrdinate($y)
    {
        if ($this->isVertical()) {
            return $this->getPointA()->getAbscissa();
        }
        return (($y - $this->getYIntercept()) / $this->getSlope());
    }
public function getAbscissaByOrdinate ( $ y ) { if ( $ this -> isVertical ( ) ) { return $ this -> getPointA ( ) -> getAbscissa ( ) ; } return ( ( $ y - $ this -> getYIntercept ( ) ) / $ this -> getSlope ( ) ) ; }
Get the abscissa of a point of the line by its ordinate

@param   float   $y
@return  float
Get the abscissa of a point of the line by its ordinate