00:01
We're given our objective function z equals 2x plus y as well as all of our constraints, and we want to begin solving this linear programming problem by graphing our constraints.
00:12
So we're given that x and y are both greater than or equal to zero, meaning that our graph will lie solely in the first quadrant.
00:21
And now i want to start graphing these lines.
00:23
So x plus y greater than or equal to 3, i can rewrite this as y is greater than or equal to negative x plus 3.
00:31
This makes it easier for me to graph, and i know that my y intercept is 3.
00:36
I have a slope of negative 1, and my x intercept would also be 3.
00:42
Similarly here, we know we can rewrite this as y is less than or equal to negative x plus 9.
00:50
So my y intercept is at 9.
00:54
I have a slope again of negative 1, meaning that our x intercept would also be at 9.
01:01
Here we have 3y is greater than or equal to negative x plus 6.
01:08
Well, we can divide both sides by 3 to isolate the y, and we get y is greater than or equal to negative 1 over 3x plus 2.
01:18
So we know that our y intercept is at 2.
01:21
We have a slope of negative 1 3rd, which means that our x intercept would be at 6, and our line looks like this.
01:32
Now the space in between these lines is our collection of feasible points.
01:41
And given these, we want to find the coordinates of all of our corner points and write them down.
01:47
So starting at this corner, i know that that point is 0 .3.
01:52
Moving here, this corner is 0 .9.
01:56
Over here, that corner is 9 .0.
02:01
This corner here is 6 .0.
02:06
And to solve for the coordinates of this corner, we're going to set the equations y is equal to negative 1 3x plus 2 as well as y is equal to negative x plus 3 equal to each other.
02:23
So negative x plus 3 equals negative 1 over 3x plus 2...