00:01
So in general, what's the equation of a circle? well, with center hk, it'll be x minus h squared plus y minus k squared equals my radius squared.
00:10
So if my center is 0 ,1, and my radius is 5, then my equation will be x minus 0 squared plus y minus 1 squared equals 5 squared.
00:24
And i want to find out what quadrant these two points intersect.
00:28
So how can i figure this out? well, what i could do, i could replace y with x plus 1, get an equation with just one variable.
00:38
So x minus 0 squared will be x squared plus x plus 1 minus 1 squared equals 5 squared, plus 1 minus 1, those end up canceling.
00:48
So i just have 1x squared plus another x squared, 2x squared equals 25.
00:54
I could divide by 2 to both sides...