Bob-Joe-Sam, Sam-Joe-Bob, Bob-Sam-Joe, Sam-Bob-Joe, Joe-Bob-Sam, Joe-Sam-Bob
Hope this helps
While since Rajeev is already below the surface by 12.6 ft it’ll be negative (-12.6) and since he went down another 8.7 ft it’ll just be minus since he is still going under, so -12.6-8.7 will be your answer. :)
=6x + −5 + 4 x 2 + 2x + −2
=(4 x 2) + (6x + 2x) + (−5 + −2)
=4 x 2 +8x + −7
Answer - 4 x 2 + 8x + −7