sed to replace value in .bashrc
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I have the following line in my .bashrc:

APP_HOME=/home/user/app/1.0;export APP_HOME; ## ADDED BY INSTALLER - PLEASE DO NOT EDIT OR DELETE THIS LINE

I want to replace APP_HOME=/home/user/app/1.0 with a different path, say /home/user/app/2.0 this could really be anything. 

I have the following:

sed s,APP_HOME=,"/home/user/app/2.0", -i ~/.bashrc

However, what I get in the file is the replacement path appended to the original. What am I doing wrong?