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

Distance travelled = Area under the graph

Eg. in figure 1, you'd calculate the area of triangles A and C, as well as the area of rectangle B. So:
A = 0.5 x B x H
= 0.5 x 10 x 20
= 100m
B = B x H
= 20 x 20
= 400m
C = 0.5 x B x H
= 0.5 x 40 x 20
= 400m

Add everything ~400 + 400 + 100 = 900m

Figure 1