okokokok, I didn't explain it well enough. (I think my calc teacher made it up herself.)

"X" equals negative "b" Yes, you ignore the "pick-up" notes. "X" would be on the second note otherwise.

"b" squared minus 4 "a" "c" "Squared" is only one syllable, but I think the main confusion is that 4 is sung over 2 notes.