Please help me, I'm stuck, thank you!

you should be able to work this out very easily for yourself.

Try putting it into here and see what happens

https://www.desmos.com/calculator

(x - 3)^2  + y^2  =  10

x^2 - 6x  + 9  + y^2  =  10

1x^2   + 1 y^2  - 6x   - 1   =   0

When  we have the form

Ax^2  + By^2  +  Cx   + Dy  +  E    =   0

If A  = B      (and E  is negative)     then we  have a circle

It was already in the most obvious form Chris.

$(x-3)^2+y^2 =\sqrt{10}^2\\ centre(3,0)\;\;radius \sqrt{10}$

If the kid looked at his formula notes.

Or if he went to desmos and graphed it, he would have known that.

I give partial answers for good reasons.