Mirror, Mirror Puzzle

The Puzzle:

If you continue shading the squares so that the two dotted lines become lines of symmetry (mirror lines) of the completed diagram, how many squares will be left unshaded?

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-\./^\./-


Do you have the answer? Check against our solution!

Our Solution:

If you continue shading the squares so that the two lines become mirror lines, we get this:



(Note: I have shaded the new squares differently just so that you can see where they go.)

The number of squares left is then 9.