Derivative of Dirac distribution in $\mathbb{R}^2$

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Consider the Dirac delta distribution on $\mathbb{R}^2$.

For an exercise I need to calculate the partial derivative $\frac{\partial}{\partial x}\delta(x,y) $ and $\frac{\partial}{\partial y}\delta(x,y)$

Let $\phi \in \mathcal{D}(\mathbb{R}^2)$

$\int_{\mathbb{R}^2}(\frac{\partial}{\partial x} \delta(x,y)) \phi(x,y)\, dx\,dy$

Using polar coordinates I get

$\int_{\mathbb{R}^2} ( \frac{\partial}{\partial r} \delta(r) ) \phi(r,\alpha)\, dr\,d\alpha=\delta(0)\phi(0,0)-\int_{\mathbb{R}^2} \delta(r) \partial_r \phi(r,\alpha)\,dr\,d\alpha$

I am not really sure on how to Continue