I only need the explanation

1.two more than the quotient of a number and 6 is equal to 7 use the c for the unknown number translate the sentence into an equation

The serenity and the mystic are sail boats. the serenity and the mystic start at the same point and travel away from each other in opposite directions. the serenity travels at 16 mph and the mystic travels at 19 mph. how far apart will they be in 3 hours?

Astudent showed the steps below while solving the inequality |x-4|< 1 by graphing.