00:01
Okay, so we're going to find the center radius of the circle here.
00:05
We're going to do a couple of completing the squares.
00:09
So to start, i'm going to rearrange these so i can put x squared and 2x next to each other.
00:15
And i'll put plus a little bit space here.
00:18
And then i'll have a plus y squared and minus 12y and then plus another little space here.
00:25
And that equals zero right now.
00:27
So to do my completing the square, so i'll take this 2x.
00:31
So start with that.
00:32
2 divided by 2 is 1.
00:34
1 squared is 1.
00:35
So i'm going to add one here, which means i am also adding one to the right side of the equation.
00:40
Negative 12 does the same thing.
00:42
So negative 12 divided by 2 is a negative 6.
00:45
Negative 6 squared is a positive 36.
00:48
So that will give me 36 here.
00:51
And since, again, since i'm adding 36 on the left side, i need to also add it to the right side.
00:57
Now i can factor both of these as two separate things.
01:00
A whole reason for completing the square is it follows this pattern of x plus one to the second power because one times one is one one plus one is two...