Question 389607
  <pre><font size = 3 color = "indigo"><b>
Hi,         
Note: roots of an equation are found when y = 0
     x^2 - 4 = 0
       x^2 = 4
        x = ± 2 

 {{{drawing(300,300, -6, 6, -6, 6, grid(1),
circle(2, 0,0.3),
circle(-2, 0,0.3),
graph( 300, 300, -6, 6, -6, 6,x^2-4))}}}