import math


def find_line_through_point(center, theta, length):
    """Find the coordinates of the start and end of a line passing through the 
    point center, at an angle theta to the x coordinate, extending a distance
    length from the center."""

    r = length
    cx, cy = center

    xo = int(r * math.sin(theta))
    yo = int(r * math.cos(theta))

    line_start = cx, cy
    line_end = cx + xo, cy + yo

    return line_start, line_end