Verified Answer :

x² - 169 = 0 
x = ?

 Add 169 to both sides.

x² − 169 + 169 = 0 + 169x² = 169
Square root
 
x = ± √169

x = 13 or x = −13

x can be 13 or -13.

x²-169 = 0
Factorizing it,
(x+13)(x-13) = 0

Therefore,
x = ±13