>> --to know the time. Now remember we could go down any column or cross any row, you know. In the previous situation we went across the top row. But here I see another 0. Ad just for practice let's use this 0, you see, we get some mileage out of using the 0 entries because items go out algebraically and makes life easier for us. Let's go down this column. So here is what I'm doing. I thinking, 2 times cofactor, so it's 2 times. Now, I've gotta think about the sign pattern here. Oh well, I'll march up over here and reproduce that sign pattern I had attached to the other one and it was plus, minus, plus and then minus plus down this way and then plus minus here and then minus plus, just alternating sign pattern. So I'm going down this column and so I'm using that sign pattern. So let's see, the sign minus. Alright, and now the determinant, let's see, the determinant. We take this item too. We take out row and column involving that 2 and we have the 3, 4, 2, 1. 3, 4, 2, 1. And then plus--I say plus, you know, we're just kinda adding as we go but we're adding and here is the negative 1 factor and the other factor involves a sign and a determinant. Okay, the sign involved with this entry from over here is plus. So I don't need to write anything. And now the determinant takes out row and column and we have 0, 4, 1, 1. And then boom, we're down here with 0. And so it's plus 0 times--now who really cares what this is. For emphasis, I'll put it in this one last time but generally we wouldn't even write anything here because we don't need to. So it's times, let's see, the sign associated with the entry is minus and the determinant is, let's see, the determinant of a matrix, take out row and column and we have 0, 3, 1, 2. So that's the idea. And then back over here we saw to make the calculations. We have, let's see, this minus sign now, I'll just put over here and we have this as times. The determinant is 3 minus 8, 3 minus 8, that's negative 5. And then here we have, let's see, negative 1 times 0 minus 4, negative 4. And that rascal goes out. So we simplify here. This becomes 10 and then plus 4, 14 as expected.