I'm kind of freaking out right now about finding the gradient on a map because my teacher told me that when you measure the straight line distance on a map, it gives you the hypotenuse of the triangle. Therefore, to find out the gradient, you would have to use Pythagorus' theorum to find the horizontal distance. Personally, I think that sounds completely wrong, because OS maps don't take contours into account when mapping distance. Can anybody help me - does the straight line distance = the horizontal distance between two points, or is it equal to the hypotenuse?
I don't know if any of that made sense...