Can someone please help me with number 2?I don't know what I did wrong.

Part A

Let's say point P is the starting point and point Q is the endpoint

x = one-way distance from P to Q, and vice versa

The goal is to find x, then compute 2x to find the round trip distance traveled.

We'll use this idea

distance = rate*time

which solves to

time = distance/rate

So when going from P to Q, the driver is going 70 mph and travels x miles

So the driver does this for distance/time = x/70 hours.

When going back, the driver slows down to 55 mph so the time taken here is x/55 hours.

The total time values add to x/70 + x/55 hours

Set this equal to the total driving time of 7 hours and solve for x

x/70 + x/55 = 7

70*55*(x/70 + x/55) = 70*55*7

70*55*(x/70) + 70*55*(x/55) = 26,950

55x + 70x = 26,950

125x = 26,950

x = (26,950)/125

x = 215.6 which is the one-way distance in miles

which then means,

2x = 2*215.6 = 431.2

Therefore, the total distance traveled is 431.2 miles

Part B

To find the duration of each trip, we simply need to evaluate x/70 and x/55. Those are the durations when going 70 mph and 55 mph respectively. These durations are measured in hours.

x/70 = (215.6)/70 = 3.08

x/55 = (215.6)/55 = 3.92

Note how 3.08+3.92 = 7 to help verify the answers.