To find the distance travelled, look at the area under the graph. In the first 10 seconds this is the area of the triangle, ½ × 10 s × 40 m/s = 200 m. From 10 to 20 seconds this is the area of ...

To calculate the gradient of a straight-line graph: Choose two points on the line that are far apart. Using a ruler, draw a right-angled triangle from one point to the other. Use the y-axis scale ...