

find the equation of the set of points P the sum of whose distance from A(4,0,0) and B (-4,0,0) is equal to 10
Please refer to the below link for the video solution of your question at 46:03 min.
https://www.youtube.com/watch?v=Swv7OxwlSYo&list=PLCzaIJYXP5YeeONYJkMpkqZtW3jvx7pWf&index=73
