which function is graphed?

The line extends along the first and fourth quadrants and passes through the points (3, 3), (6, 0), (8, negative 2), and (10, negative 4). A closed dot is shown at the point (3, 3). The parabola extends along the first and second quadrants and passes through the points (3, 15), (2, 10), (10, negative 2), and (negative 4, 20). An open dot is shown at the point (3, 15). The vertex of the parabola lies at (0, 6).