# Implicit differentiation to find the slope

## Homework Statement

$$(x - h)^2 + (y - k)^2 = r^2$$
where h,k and r are constants

## The Attempt at a Solution

$$\begin{array}{l} \frac{d}{{dx}}\left[ {(x - h)^2 + (y - k)^2 } \right] = \frac{d}{{dx}}r^2 \\ 2(x - h) + 2\frac{{dy}}{{dx}}(y - k) = 0 \\ \Rightarrow \frac{{dy}}{{dx}} = - \frac{{(x - h)}}{{(y - k)}} \\ \end{array}$$

Is my work correct?
Thank you

## Answers and Replies

looks good to me =P

Defennder
Homework Helper
Yeah it seems all right.