Broken 5/16 line from filter to water tank in fridge

Others have described how to do this repair better. I will simply add - if you're cutting the line inside the fridge to repair/replace be sure to check as their are two (2) clear 5/16th lines. Once goes from the solenoid to the tank inside the fridge and another from the tank up to the filter. They're identical and side by side. Remove the drawers and foam covering the one line to make sure you cut the right one...otherwise you will be ordering a 2nd water tube union like I did.