Question

What is the solution of n^2 - 49 = 0

Answer 1

N² - 49 = 0
   + 49  + 49
        n² = 49
         n = +7

The solution to the problem is {7, -7}.

Answer 2

So $n^{2} - 49 = 0$
Add 49 from 0 and you get
$n ^{2} = 49$
Only $7^{2}$= 49 so n = 7