Each week, Rosario drives to an ice-skating rink that is 60 miles away. The round-trip takes 2.75 hours. If he averages 55 miles per hour on his way to the rink, which equation can be used to find x, the number of miles per hour he averages on his way home?

The answer to your question is x = 4d/t - S1

Step-by-step explanation:

Data

total time = t = 2.75 hours

Initial speed = S1 = 55 mi/h

Final speed = x

distance = d = 60 mi

Formula

speed = distance / time

Average speed = (Initial speed + final speed)/2  or

                          = (S1 + x)/2

Substitution

                             (S1 + x)/2 = 2(d) / t

Solve for x

                             x = (2d/t)2 - S1

Simplification and result

                              x = 4d/t - S1

answer: (c) m∠qpo + (2x + 16)° = 180°

step-by-step explanation:

the opposite angles of a quadrilateral are supplementary.

so, ∠o + ∠q = 180°   and   ∠p + ∠r = 180°

since ∠r = 2x + 16°, we can use substitution as follows:

∠p + ∠r = 180°

∠p + (2x + 16)° = 180°