Explanation:
Hey, there!!
Let's simply work with it,
The given coordinates are, P(-2,3) and Q(5,4).
Now, finding the P' and Q'.
Reflection on x- axis .
P(x,y)---------> P' (x,-y)
P (-2,3)----------> P'(-2,-3)
Now, let's find Q'
Reflection on y-axis.
Q(x,y)----------> Q'(-x,y)
Q(5,4)---------> Q'(-5,4)
Now, The points are P'(-2,-3) and Q'(-5,4)
By distance formulae,

Putting their values,


Simplifying them we get,

Therefore, the distance between P'and Q' is root under 58 units.
Hope it helps...