<u>Answer:</u>
An equation that relates the speeds of the two legs of the trip

<u>Explanation:</u>
Given, we have to use x to represent the speed on the second leg
Speed on first leg when increasing your speed by 40 mph will be (x-40)
Distance is given as 640 miles and time is calculated as

According to the question, increasing speed saved four hours
Therefore, the equation that relates the speeds of the two legs of the trip will be

I don't know how to answer this because i don't know the other numbers. But I can tell you to find a missing angle all the angles must add up to 180. So just add the other numbers and subtract the answer from 180 then you should get an answer.
Yes, 4 goes into 632 158 times.
hope this helps
28 rounds up to 30.
32 rounds down to 30.
21 rounds down to 20.
38 rounds up to 40.
42 rounds down to 40.
30 + 30 + 20 + 40 + 40 = 160
Answer: C. 160 min