class file has wrong version 50.0, should be 48.0 error

[hybrid]

Hi,

I'm new to Java so I was wondering if anyone could help me with the following error that I keep getting:

D:\Implementation\Name\PropertyAgent.java:14: cannot access House
bad class file: .\House.class
class file has wrong version 50.0, should be 48.0
Please remove or make sure it appears in the correct subdirectory of the classpath.
private House addHouse;
^
1 error

how could I fix it? Thanks in advance