Answer
x=-2
Work Step by Step
Factor the trinomial.
x$^2$+4x+4=0
(x+2)(x+2)=0
Set each variable factor as equal to zero and then isolate the variable to find the solutions.
x+2=0 or x+2=0
x=-2 or x=-2
Enter the original equation into your graphing utility to observe that the graph crosses the x-axis at -2.