Question 760851
(1 - x)^2 = 4
 Square root both sides
 1 - x = sqrt4
 1 - x = 2
   - x = 2 - 1
   - x = 1
     x = -1
Proof
(1 - x)^2 = 4
(1 - (-1)^2 = 4
 (1 + 1)^2  = 4
    (2)^2 = 4
       4 = 4
Hope this helps.
:-)