Question

Which equation has the same solution as x^2 - 6x - 12 = 0?
(1) (x + 3)^2 = 21 (3) (x + 3)^2 = 3
(2) (x - 3)^2 = 21 (4) (x - 3)^2 = 3

Answer 1

(2)
Because ( x - 3 )^2 = x^2 - 6x + 9 ;
               x^2 - 6x + 9 = 21 ;
               x^2 - 6x - 12 = 0 ;