00:01
Okay, we're turning these tables into matrices in order to help us calculate the matrix product a times b.
00:10
So let's start with our matrix here.
00:14
We're going to have, let's call this matrix a, and we're going to have student one here and student two here.
00:23
We'll have college a at the top and college b here.
00:27
And we'll see how that works for us in a second.
00:29
So we're just changing this table into this array of numbers.
00:34
And then matrix b over here, we're going to have a row of a and a row of b, so 86 and 65.
00:46
And before we can multiply these together, we want to make sure that not only do our dimensions match, but our labels match.
00:53
So remember that if i'm going to multiply a two by two together times a two.
01:00
Two by one, we can only do this multiplication, this matrix multiplication, if the two inside numbers match.
01:08
The two inside numbers match.
01:11
And when we do that, we need to make sure that the columns, the columns of the first, so the columns a and b, have the same units as the rows of the second...