(Transcript of audio with descriptions. Transcript includes narrator headings and description headings of the visual content)
(Speaker)
To help us identify the average slope for this particular segment we're going to start by labeling the points 3%, 6%, and 1.5%, 5%.
(Description)
The coordinate plane with Airborne pollutants as a dependent variable and Economic Growth as an independent variable is drawn. The Airborne pollutants are measured from 0 to 8 percent on the y-axis. The Economic Growth is measured from 0 to 11 percent on the x-axis.
(Speaker)
The first point we want to label corresponds with an economic growth rate of 3% and a level of airborne pollutants of 6%. To do this, we first find 3% on the horizontal axis.
(Description)
3 percent on the horizontal axis is highlighted.
(Speaker)
After finding 3% on the horizontal axis, we will draw a dotted line up to 6% on the vertical axis.
(Description)
6 percent on the vertical axis is highlighted. A dotted vertical line from 3 percent on the x-axis up to 6 percent on the y-axis is drawn.
Another dotted horizontal line from 6 percent on the y-axis to 3 percent on the x-axis is drawn. Both lines intersect at the point with coordinates, 3 percent and 6 percent.
(Speaker)
We will label this point A.
(Description)
Point, A, with coordinates, 3 percent and 6 percent, is labeled.
(Speaker)
Now we want to label the second point. The problem says Economic growth fell from 3% to 1.5%, which causes air pollutants to fall from 6% to 5%.
So we start by finding 1.5% on the x-axis and then go up to 5% on the y-axis.
(Description)
1.5 percent on the horizontal axis is highlighted. A dotted vertical line from 1.5 percent on the x-axis up to 5 percent on the y-axis is drawn. Another dotted horizontal line from 5 percent on the y-axis to 1.5 percent on the x-axis is drawn. Both lines intersect at the point with coordinates, 1.5 percent and 5 percent.
(Speaker)
We will label this point B.
(Description)
Point, B, with coordinates, 1.5 percent and 5 percent, is labeled.
(Speaker)
To find the slope using the arc method, we must take the change in y divided by the change in x. We can do this by calculating the difference in the y value going from point A to point B. Doing so yields a change in y of 1 unit, or 6 minus 5.
(Description)
A vector from point, A, with coordinates, 3 percent and 6 percent, to a point with coordinates, 3 percent and 5 percent, is drawn. It is labeled as change in Y equals 6 minus 5 equals 1.
(Speaker)
Next we need to find a change in the independent variable. Doing so yields a change in x of 1.5 units, or 3 minus 1.5.
(Description)
A vector from a point with coordinates, 3 percent and 5 percent, to point B with coordinates, 1.5 percent and 5 percent, is drawn. It is labeled as change in X equals 3 minus 1.5 equals 1.5.
(Speaker)
The final step is to divide the change in y by the change in x. This gives us a slope of 1 divided by 1.5, or a slope of two-thirds.
(Description)
A line between the points, A, and, B, is drawn. It is labeled as Slope equals the change in Y divided by the change in X equals 1 divided by 1.5 equals 2 divided by 3.