The audience likes to guess what the actor is doing. It incorporates audience interaction and that wouldn't be possible if the actors simply imitate physical actions.
The correct answer is 3 + 6x. Heres why: Add or subtract all of your variables x + 2x + 3x = 6x. Now add or subtract your numbers 7-4= 3. 6x + 3 or 3 + 6x.
