00:01
So we know our x is equal to 3, radical 3, and we know our y is equal to negative 3.
00:10
So now we can find r.
00:12
R squared is equal to x squared plus y squared.
00:21
So we plug in our x value, and plug in our y value, we get our r squared is equal to 27 plus 9, or just 36.
00:52
Now we take the square root of both sides.
00:56
We get r is equal to plus or minus 6.
00:59
Now we want our r to be positive because our question requires that our radius be positive.
01:04
So that's why i chose 6.
01:08
Now to find our angle, we could use the identity that tan of theta is equal to y over x.
01:17
I'm not going to do that because that kind of makes it hard to use the unit circle.
01:22
Instead, i'm going to use our x.
01:25
Is equal to y, or excuse me, our r times cosine theta...