Fixes #3594, solutions are natural numbers (#3597)

exercises/practice/square-root/.docs/instructions.append.md

@@ -6,7 +6,7 @@
 Python offers a wealth of mathematical functions in the form of the [math module][math-module] and built-ins such as [`pow()`][pow] and [`sum()`][sum].
 However, we'd like you to consider the challenge of solving this exercise without those built-ins or modules.
 
-While there is a mathematical formula that will find the square root of _any_ number, we have gone the route of only testing [natural numbers][nautral-number] (positive integers).
+While there is a mathematical formula that will find the square root of _any_ number, we have gone the route of having only [natural numbers][nautral-number] (positive integers) as solutions.
 
 
 [math-module]: https://docs.python.org/3/library/math.html