Answer
This is the meaning of the notation:$ \lim\limits_{x\to8}f(x)=25$:
As the input approaches closer to 8, the output approaches closer to 25.
Work Step by Step
If you graph the function $f$, then you can see that the y value of graph gets closer and closer to 25 when the x value gets closer and closer to 8, graphically proving this limit.