40 mph would be 120 miles in 3 hours (120/40)
80 mph is 120 miles in 1.5 hours(120/80)
3 - 1.5 = 1.5, not 3 hrs
Change the speed to 20 mph( 1/2 the speed) to double the hours.
20 mph = 6 hours(120/20)
40 mph = 3 hrs(120/40)
6 - 3 = 3 hours difference
Answer:
gimme the rest of the question then i can properly answer this question
Step-by-step explanation:
5×21/-1+9
105/-1 +9
-105 +9
-96
hope that helps
Answer:

Step-by-step explanation:
We need to find the value of x so that the value of given function becomes 21 .
We have ,

Now , for finding x ,
Step-by-step explanation:
7h + 4 > 5 - 5h
7h + 5h > 5 - 4
12h > 1
h > 1/12