How do I find a gradient?

Question

I have been puzzled for hours. Every text book tells me 'rise over run', and draws a little triangle on the graph. How do I know where to put the triangle? I have a physics exam in three hours.... so if someone could help i'd be eternally greatful!

Answer 1

it doesn]'t matter where you put the triangle, just place it with the diagonal side on the line in question

Answer 2

"Rise over run" is the slope of the line. The triangle (the two sides other than the portion of the line) shows the "rise" and the "run", separately, as a line going up or down and a line going right or left, from the first point to the second point.

1. Start at a point on the line.

2. Draw the "rise" line from there, based on the number for "rise" and going up (if positive) or down (if negative) and ending up at an intermediate point above or below the starting point.

3. From this intermediate point, draw the "run" line based on the number for "run" and going right (if positive) or left (if negative), ending up at a second point on the line.

Answer 3

use over half of the graph as x axis measure the distance upwards (y), and use m = y/x

you can use any bit, best to use over half of the graph

Answer 4

put a triangle anywhere... but a bigger triangle means it will be more accurate.

Basically... gradient is: change in y divided by change in x.

So after making a right angled triangle where you have a horizontal line, a vertical line, and the line which you started with on the graph... you would divide the vertical side by the horizontal side and that will give you your gradient.