# How do you differentiate x^2 + y^2 = 4?

${x}^{2}$ + ${y}^{2}$ = 4
2x + 2y $\frac{\mathrm{dy}}{\mathrm{dx}}$ = 0
2y$\frac{\mathrm{dy}}{\mathrm{dx}}$ = - 2x
$\frac{\mathrm{dy}}{\mathrm{dx}}$ = $\frac{- 2 x}{2 y}$