Question 68803
Whenever you take a square root of a squared value, you're simply undoing the operation that happens when you square a number. For instance, {{{3^2}}} equals 9 and when you take the square root it becomes 3 and -3 (since {{{(-3)^2=9}}}).

In this case, the square root of {{{(28n)^2}}} is simply {{{28n}}} and {{{-28n}}}