Explanation:
Hey, there!!
Let me explain you very simply, ok.
Here, according to the question,

X is square so, which finding the value of x you must take it to the right side (in root form ). so,

Now, as we know that,
sq.root of 25 = 5
sq.root of 144 = 12
Now, you write it as,


Now, square root and (5/12) square ( square root , square gets cancelled).
You will get as,

And its your simplified answer.
Hope it helps...