Panel 1: Teacher in front of black board (with latin declination of "hic"): "Well, class. I hope you all learned the quadratic formula. Today's test cannot be passed without it." -- Panel 2: A naked person (only the back is visible) runs through the scene shouting "STREEEEEEEEEEAK!!!", having the quadratic formula (-b +- sqrt(b²-4ac))/(2a) written on his back. The teacher is shocked. -- Panel 3: The person is gone. The teacher looks confused.