Answer:
Add 36. The factored form is [tex](x+6)^2[/tex].
Step-by-step explanation:
A perfect square is a trinomial that factors into the form [tex](x+a)^2[/tex]. To find the value to add to it divide 20 by 2 and square it.
12/2 = 6
6*6 = 36
This means c=36. The factored form is [tex](x+6)^2[/tex].
