Step 1: Open up the image you would like to resize. File > Open.
Step 2: This is a very simple simple step, right click on the document title bar and select "Image Size..."
Step 3: A new window will pop up, you should see this.

Change the width to anything you would like.

If you notice, it automatically adjusts the height of the image so your image doesn't become distorted looking. This
feature is called "Constrain Proportions."
Step 4: Now look at the image below, it has been resized! You can go to File > Save As, and save the file as
"Jpg." enjoy!