[NTG-context] adding an icon (flushed left) in a displayed formula with equation number

All, We have: \placeformula[eq:commonb] \startformula (1)^2+(\sqrt{4x+13})^2=(2x)^2, \stopformula This gives us a centered equation with an number pushed to the right edge of the page (I probably should say text area). What we'd like to do, just in this one example (not globally), is add a little "smiley face" icon on the same line as the displayed equation and equation number, but pushed to the left edge of the page (I probably should say text area). Possible?