I'm stuck on this question:

I am not looking for the entire answer, just where to start. Would the first thing to do be to solve for $\displaystyle y$, and then take the derivative?In the curve to which the equation is $\displaystyle y^2+x^2=4$, find the value of $\displaystyle x$ at those points where the slope = 1.

$\displaystyle y^2+x@=4$

$\displaystyle y^2=4-x^2$

$\displaystyle y=\pm\sqrt{4-x^2}$

is this right so far? Thanks.