Question

The image is composed of separate black pieces. What is the least number of pieces that must be moved and/or rotated and/or flipped to make the figure mirror–symmetric about the central vertical axis? 

Hint:

To minimize moves for mirror symmetry: pair pieces across the axis and count only the mismatched pairs/solitaires. Each independent mismatch requires at least one move/flip/rotation.

Answer 1

Step 1: Establish the axis and pair up pieces.
Draw the dashed central vertical axis. Every piece on the left should have a mirror counterpart on the right with the same distance from the axis and mirrored orientation.
Step 2: Scan row by row.
- Head/ears: two ear triangles and the central crown show one mismatch on the upper right that lacks a proper counterpart on the left. \(⇒ 1\) move.
- Eye/forehead band: one trapezoid on the left has orientation mismatch with the right; correcting either side by flipping a single trapezoid fixes the pair. \(⇒ 1\) move.
- Wing columns: inspect each vertical column of chevrons. Two columns (one left, one right) have a displaced chevron each. Moving one chevron per column restores the pairings. \(⇒ 2\) moves.
- Lower body/tail: a small triangular piece on the lower left has no mirrored mate; moving it to the symmetric position resolves both sides. \(⇒ 1\) move.
- Edge flares: one side feature near the bottom right is rotated relative to its left mate; rotating that single piece fixes the mismatch. \(⇒ 1\) move.
Step 3: Minimality.
Each action above corrects exactly one asymmetric pair (or an unmatched solitary piece) without creating a new mismatch. No fewer actions can resolve all five independent mismatches.
Final Answer: \[ \boxed{6 \text{ pieces}} \]