Answer:
Distance = 162 units
Time 9 minutes
Step-by-step explanation:
The distance from -81 to 0 is 81 units
The distance from 0 to 81 is 81 units
The total distance is 81+81 = 162 units
OR
81-(-81) = 162
Distance = 162 units
Distance = rate * time
We know the distance and the rate = 18 units per minute
162 = 18* time
Divide each side by 18
162/18 = 18/18 * time
9 = time
The time is 9 minutes
