There are 2 shapes on a 8x8 grid. Which shape is closest to the red 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: red right_triangle at (0, 4)
Distance from target shape to yellow right_triangle at (1, 7): 4
Closest shape is the yellow right_triangle at (1, 7) with distance 4</think>

<answer>(1, 7)</answer>