A truck left Haifa. During the trip it stopped twice.
The graph below describes the distance from Haifa as a function of time elapsed since the start of the trip.
The Graph
The Table
b. During which time intervals did the truck not travel? Explain.
Choose the correct answer:
1Between hour 0 and 1 and between hour 4 and 5
2Between hour 1 and 2 and between hour 3 and 3.5 (because the graph is horizontal - the distance does not change)
3Between hour 5 and 7 (because the graph is going down)
4The truck traveled the entire time without stopping
c. Did the truck return to Haifa? Explain.
Choose the correct answer:
1Yes, the truck returned to Haifa because at time x=7 the distance is y=0
2No, the truck did not return because at the end it remained 100 km away
3It cannot be determined from the graph
4Yes, because it stopped twice along the way
d. What was the maximum distance from Haifa during the trip?
Choose the correct answer:
1100 km
2150 km
3200 km
4250 km
e. Is it possible that at two different times the distance from Haifa was the same?
Choose the correct answer:
1Yes, because on the way there and on the way back the truck passed through the same distances
2No, each time has a different distance
3No, because it is a function
4Only during the stops
f. Is y (the distance) a one-to-one function of x (the time)?
Choose the correct answer:
1Yes, because each time corresponds to a unique distance
2No, because there are distances that correspond to more than one time (e.g., 150 km on the way there and back)
3Yes, because the graph goes up and down
4Cannot be determined
Reminder: A one-to-one function is a function in which each y value corresponds to at most one x value.
In other words: every horizontal line intersects the graph at most at one point.