There are 3 shapes on a 9x9 grid. Which shape is closest to the brown right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: brown right_triangle at (2, 6)
Distance from target shape to gray right_triangle at (6, 4): 6
Distance from target shape to green right_triangle at (5, 6): 3
Closest shape is the green right_triangle at (5, 6) with distance 3</think>

<answer>(5, 6)</answer>