00:07
So we are given a right triangle, and in part a, we're asked to find the length of each side of this right triangle.
00:19
And in part b, we're asked to show that these lengths satisfy the pythagorean theorem.
00:31
We see that a diagram of this triangle in the cartesian plane is given in exercise 24 of this section.
00:42
I'm going to simplify the diagram by simply giving the vertices of the triangle.
00:50
So looking at our diagram, we see that our triangle has the vertices, negative 1, 1, 9 -1, and 9 -4.
01:24
We also see that this is indeed a right triangle.
01:33
Now in part a to find the length of each side of the right triangle, first of all, let's label each of these vertices.
01:45
So we'll label vertex a as negative 1 -1.
01:51
We'll label vertex 9 -1 as b and vertex 9 -4 as c.
02:04
To find the length of side a -b, we use our distance formula for the distance between two points, and therefore this is the distance from negative 1 -1 to 9 -1, which is the square root of negative 1 minus 9 squared plus 1 minus 1 squared, which is equal to the square root of negative 1 minus 9 squared is, that's negative 10, so the square root of negative 10 squared plus 1 minus 1 is 0 squared, which is still 0.
03:11
And so we have negative 10 squared is 100, and the square root of 100 is again 10.
03:18
So the length of side ab is 10.
03:26
Likewise, the length of side b, c is the distance between points b and c, or the distance between points 9 -1 and 9 -4.
03:46
And this is the square root of 9 -9 -2 -squared plus 1 -4 squared, which is the square root of 0 -2, which is 0, plus 1 -4, which is negative 3 squared.
04:07
So this is 3...