Answer:
A. x²+y²=45
Step-by-step explanation:
The equation of a circle centered at the origin is of the form:
[tex] {x}^{2} + {y}^{2} = {r}^{2} [/tex]
where r is the radius of the circle.
Among the given options, the only equation that looks like this is
[tex] {x}^{2} + {y}^{2} = 45[/tex]
The rest are equations of a circle with center not at the origin.
The correct choice is A.