1.8 determine the distance travelled from the area between a velocity-time graph and the time axis

The area under the line in a velocity-time graph represents the distance travelled. To find the distance travelled in the graph above, we need to find the area of the light-blue triangle and the dark-blue rectangle.

The area of light-blue triangle; the width of the triangle is 4 seconds and the height is 8 metres per second. To find the area, you use the equation:
area of triangle = ¹⁄₂ × base × height
so the area of the light-blue triangle is ¹⁄₂ × 8 × 4 = 16m. 

Area of dark-blue rectangle; the width of the rectangle is 6 seconds and the height is 8 metres per second.
 So the area is 8 × 6 = 48m.

Area under the whole graph; the area of the light-blue triangle plus the area of the dark-blue rectangle is:
16 + 48 = 64m covered by the object.