Set image dimensions using markdown

When embedding an image using the markdown editor, is it possible to specify the image dimensions? It seems that both of these do not work:

Inline HTML:

<img src="https://​​i.imgur.com/​​25Magmb.png“ width=”123” height=”123″>

Some markdown variant I found on stackoverflow:

![alt text](https://​​i.imgur.com/​​25Magmb.png =123x123)