What are the roots of the quadratic equation x² + 4x + 4. how many roots are there.

If we set the equation equal to 0, we can factor it to find its roots:

x² + 4x + 4 = 0
(x + 2)(x + 2) = 0
x = -2

This graph has one root, a double root, at -2.  This means that a single point, which must be the vertex of the parabola, touches the x-axis at (-2, 0)