Trouble with formulation of an analytic geometry question

Question

I'm having trouble understanding a certain question, so I am asking for an explanation of it. The question is asked in a different language, so my translation will probably be mistake-ridden, I hope you guys can overlook the mistakes (and of course correct them):

Show that for each $ a $ the circle $ (x-a)^2 + (y-a)^2 = a^2 $ touches the axes.

This is literally how the question is formulated, I'm sure that it isn't a hard question so if one of you can explain what they mean by this question I would appreciate it!

Answer 1

The equation $$(x-a)^2 + (y-a)^2 = a^2$$ defines a circle in the plane. The question just asks you to prove that circle touches the coordinate axes of the plane.

(Hint for the question: Where is the center of the circle defined by that equation, and what is its radius?)

Answer 2

A slightly different take on your question would be to realize that if your circle touches the $Y$ axis, it must do so at a point $(0, y)$. Substitute $x=0$ in the equation of your circle; can you find a value for $y$? The answer for touching the $X$ axis can be found in a similar way.