00:01
In this question, we're told that the current oil reserves measure in at 2170, 2 ,170 billion barrels, and that on average, every year they decrease by 19 billion barrels.
00:17
And we want to first try to find a linear equation to model this behavior.
00:24
So for part a, we're trying to find an equation of a line.
00:28
So the equation of a line is y equals mx plus b.
00:33
We're going to use r to represent the oil reserves at any given moment.
00:41
Now the slope is going to be this value right here.
00:45
We're decreasing by negative 19 billion barrels per year.
00:52
So we're going to keep this m is going to be negative 19.
00:58
And then our x value is going to be the number of years, so i'm going to put t for time.
01:07
And then our y intercept, the value that we start at, is going to be the 21 billion barrels of oil.
01:16
So we're going to have 2 ,170 represent the y intercept.
01:22
So this is going to be our linear equation that models this.
01:26
And i'll just make a note that r is in, billions...