Question 397563
   <pre><font size = 3 color = "indigo"><b>
Hi, 
f (x)= x^2 + 6x +9
factored
f (x)= (x+3)(x+3)
|setting f(x) = 0 to find the root(s) of the equation
 0 = (x+3)(x+3)     |note factors are indentical is this example
       (x+3)= 0  
         x = -3   
PT(-3,0) is the x-intercept and the vertex of the parabola as well in this ex
 {{{drawing(300,300, -6, 6, -6, 6, grid(1),
circle(-3,0,0.3),
graph( 300, 300, -6, 6, -6, 6, x^2 + 6x +9
))}}}