00:01
Okay, i'm not going to try to reproduce the drawing.
00:04
It's trying very specifically.
00:06
So i'm going to point out that our point q is minus 3, 4.
00:15
All right, and we have a circle centered at the origin that goes through this point.
00:23
Actually, it's number 1.
00:26
So the first question is, what's the equation of that circle? so it's centered at the origin.
00:33
Origin, so we know it's x squared plus y squared, that has to be the square of the radius.
00:39
It has to pass through this point, all right? so if we plug that point in, we get 25.
00:54
And number two, so we've got our point q.
01:01
We're interested in another point t, which is the point 0 .50.
01:08
It's the point where the circle crosses the positive x -axis.
01:13
And since we know its radius is 5, that's going to be where that point is.
01:18
And so we want the distance between q and t.
01:34
Excuse me, that's plus 3 minus 4.
01:37
Doesn't change anything we've done.
01:39
So it's 5 minus 3 squared squared plus 4 squared.
01:46
That's the square root of 20, which is 2 times the square root of 5, which leaves it in surged form.
01:57
And then 3, we want to talk about the point that's diametrically opposite.
02:07
That's our point p, but it's diametrically opposite to q.
02:13
So it's basically the negative of it.
02:17
So p is minus 3, 4.
02:28
Then in 1 .4, we want to know, we want to find the equation of the circle centered at p that passes through the origin.
02:37
So we know its radius is still going to be 5.
02:41
So it's going to be, it's going to look like this...