Changing resolution on a photo in Google+

With my old laptop I used Gimp to manipulate images. Now that I have a Chromebook that obviously won't work. I switched over to using the image edit tool in Google+ as that's where my images reside anyway. Mostly I've been pretty happy with Google's image edit tools with one exception. I can't seem to find a way to specify a pixel based measurement for either the height or width of an image via scaling. The only thing I see is the crop tool.

I need images of a specific height/width for use on a website. Is there any way to scale images using Google+ image editor?