Study the distance-time graph given below for a car to travel to certain places and answer the questions that follow.
A) How far does the car travel in 2 hours?
B) How much time does the car take to reach R?
C) How long does the car take to cover 80 km?
D) How far is Q from the starting point?
E) When does the car reach the place S after starting?
A) Find the y-coordinate when the x-coordinate is 2.
Here, when x = 2 hours, y = 80 km.
∴ The car travels 80 km in 2 hours.
B) The coordinates of the point R are (5, 200). Since the time is represented by the x-axis, the time taken by the car to reach point R is 5 hours.
C) The x-coordinate when y = 80 is 2. Thus, it takes the car 2 hours to cover 80 km.
D) The coordinates of Q are (3, 120) and those of the starting point are (0, 0). Since the y-axis represents the distance covered, the distance of point Q from the starting point = 120 – 0 = 120 km.
E) The coordinates of point S are (6, 240) and those of the starting point are (0, 0). Since time is denoted on the x-axis, the time when the car reaches S after starting = 6 – 0 = 6 hours.