Resizing dynamic images (Flash 8)

I have searched forever trying to find out how to do this. All the tutorials or answers I find aren’t quite what Im looking for so I figure it would just be best for me to try posting.

What I want to do is load an image dynamically into a movie clip either created physically inserting it onto the stage or using .createEmptyMovieclip(). After the image has been loaded I want to be able resize the movieclip with the image inside of it, or somehow get the .height and .width of the image or the movieclip with the image in it and then have it resize keeping its proper dimensions.

Ex:
I have an image that is say, 800x600. I want to be able to load that image in dynamically into 2 seperate movieclips (one being a main display, and one a smaller thumbnail). This way I don’t have to have resize all the images into the main display size, and thumbnail size. I can just use the image and do all the work with actionscript.

I have tried using code similar to this:

_root.createEmptyMovieClip(“load_pic”, this.getNextHighestDepth);
_root.createEmptyMovieClip(“load_thumb”, this.getNextHighestDepth);

load_pic.loadMovie(“my_pic.jpg”);
load_thumb.loadMovie(“my_pic.jpg”);

load_pic.onLoad = function(success);
if(success){
this._x = this._x/2; //Hoping this would reduce the _x by half
this._y = this._y/2; //Same a above
};
};

load_thumbs.onLoad = function(success);
if(success){
this._x = this._x/6; //Hoping this would reduce the _x by half
this._y = this._y/6; //Same a above
};
};

Can this be done? Is this not the right way to do it? What would a better way to do this be? Or is the only way to have seperate folders with seperate images/sizes for thumbnails, etc.