Long ago, a treasure was buried. The map was chopped into 9 pieces that were mixed up. Your job is to assemble the 9 puzzle pieces by placing them on the grid. Click on a piece to rotate it, or drag the piece to move it. Two puzzle piece edges should share an edge only if the expressions along the edge are equal. The upper left piece of the map is already in place.

Once the maze is correctly solved, the map to a treasure will be revealed.

To solve the puzzle and assemble the 9 puzzle pieces, follow these steps:

1. Start by focusing on the upper left corner piece that is already in place. Examine the expressions on its right and bottom edges, and keep their values in mind.

2. Look for a puzzle piece that has an expression on its left edge that matches the value of the right edge of the upper left corner piece. Drag and rotate the piece if necessary, and place it to the right of the upper left corner piece.

3. Now, focus on the bottom edge of the upper left corner piece. Look for a puzzle piece that has an expression on its top edge that matches the value of the bottom edge of the upper left corner piece. Drag and rotate the piece if necessary, and place it below the upper left corner piece.

4. Continue this process of matching and placing puzzle pieces based on their shared edges and equal expressions. Look for the values of the exposed edges and find puzzle pieces that match those values. Rotate and drag the pieces as needed to fit them into the grid.

5. As you place more pieces, make sure to continually check the edges for matches and adjust the placement as necessary.

6. Keep working on fitting the remaining pieces based on their matching expressions. This might involve rotating and dragging multiple pieces to find the correct position.

7. Once all 9 puzzle pieces are correctly placed on the grid, the map to the treasure will be revealed, and you will have completed the puzzle.

Remember to observe the expressions on the edges, rotate and drag pieces, and match the values to solve the puzzle. Good luck!