00:01
We know that the general equation of a circle in standard form is given by the equation x minus h squared plus y minus k squared equals r squared, where the point h k is the center of the circle and r is the radius.
00:15
So suppose we are given the center of a circle at the point 51, and we're given its diameter to be 4 square root of 5 .5.
00:34
And we want to know the equation of the circle.
00:37
So to do that, we would just plug in these values where they would go in the equation.
00:43
However, notice we are given diameter when our equation asks for the radius.
00:48
So we know that the diameter is equal to two times the radius.
00:52
So the radius is the diameter divided by two.
00:57
So in this case, the radius would be equal to two square root of five.
01:07
So plugging this into our equation, we know that x minus h, or x minus 5 squared, plus y minus k or y minus 1 squared, is equal to 2 square root of 5 squared...