def is_inline(*points):
    """
    Checks whether all given points are on a single line. The points order
    is not important.
    
    Args:
        *points: ((float, float),)
            Collection of points to check as (x,y) coordinates.
    
    Returns:
        bool
            Returns True if all points are on a single line, False otherwise.
    """
    
    if len(points) < 3:
        return True
    
    x1, y1 = points[0]
    x2, y2 = points[1]
    
    dx1 = x1 - x2
    dy1 = y1 - y2
    
    for x2, y2 in points[2:]:
        dx2 = x1 - x2
        dy2 = y1 - y2
        if (dy1*dx2) != (dx1*dy2):
            return False
    
    return True