def get_closest_point(x0, y0, a, b, c):
    """
    Returns closest point from x0,y0 to
    ax + by + c = 0
    """

    x = (b * (b * x0 - a * y0) - a * c) / (a ** 2 + b ** 2)
    y = (a * (-b * x0 + a * y0) - b * c) / (a ** 2 + b ** 2)

    return x, y