Gandalf the Grey started in the Forest of Mirkwood at a point with coordinates (-2, 1) and arrived in the Iron Hills at the point with coordinates (-1, 6). If he began walking in the direction of the vector $\bf v = 5 \mathbf{i} + 2 \mathbf{j}$ and changes direction only once, when he turns at a right angle, what the point where he makes the turn.