The reason this is tricky is because all the other columns have all 3
possible conditional formatting slots taken, so it seems one would need to
use code for this.

I use the square root symbol (representing a checkmark) in a pulldown menu
in column A. So column A is either empty or it has this symbol. When
empty, nothing happens; but if user chooses this "checkmark" symbol, the
cells in column B to E of that row should then have a strikethrough applied
to the text in that row. Also, where would one put the vb code to do this?
I've searched the archives but so far no mention has been made on where this
type of code to augment conditional formatting should go.

tia :oD