00:01
Okay, we are going to find the area of a parallelogram with one corner p in size pq and pr.
00:07
So first, let's look at the formula for area.
00:10
It's going to be the magnitude of the cross product between two vectors.
00:16
So to come up with our vectors, we're going to have pq, and then we're going to have pr.
00:21
So for pq, we're going to take all the points in q and minus p.
00:25
So 5 minus 1, negative 3 minus 1, and 0 minus negative 0.
00:31
For r, we'll go ahead and take everything from r and subtract p.
00:36
So in negative 2 minus 1, 4 minus 1, and 1 minus negative 6.
00:43
Let's call our top vector v and our bottom 1 w.
00:47
So now to find the cross product, let's label i, j, and k...