Question

How to write an equation in standard form for a circle of other radius 3 centered at the origin

Answer 1

Answer:

$from \: general \: equation \\ {x}^{2} + {y}^{2} + 2gx + 2fy + c = 0 \\ at \: the \: origin \: \: g = 0 \: and \: f = 0 \\since \: c = {g}^{2} + {f}^{2} + {r}^{2} \\ whe re \: r \: is \: radius \\ therefore \: c = {3}^{2} = 9 \\ = > {x}^{2} + {y}^{2} + 9 = 0$

Answer 2

Answer:

What is the diameter of a circle if the radius is 3