To start Paint, click "start" (button in the left menu of the screen) and select All programs, then Accessories, and click Paint.
Add to Paint a picture. To do this, press the menu button in the quick access toolbar (in the upper left corner of the program window and click "Open". A window will open where you will see the contents of your computer. Locate the folder that contains the picture and click on it twice.
After the image appears in the Paint window, click "Change size", which can be found in the menu at the top. In the menu "resize and skew" option, select "Pixels" and "Maintain aspect ratio". Enter the desired numeric value horizontal, then the vertical value will automatically be installed. Click OK and the picture will change its size.
You can now save the result. If you wish to keep the original version of the image, then click on the menu button and select Save as. Enter the name of the picture , and select the folder in which it will be saved. If you don't need to save the original image, just right click on the disk icon in the menu. The picture with the new resolutionm overwrites the original file.