Question

Which value must be added to the expression x2 + 12x to make it a perfect-square trinomial?

Answer 1

x^2 + 12x + 36 = (x +6)^2

answer
36

Answer 2

x^2+12x=0
(ax^2+bx)=0
(b/2)^2=(12/2)^2=(6)^2=36
x^2+12x+36=(x+6)^2