Question 374913
  <pre><font size = 3 color = "indigo"><b>
Hi,
When the Discriminant is zero. There is only one solution.  x = -b/2a
for example
y = x^2 + 2x + 1
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
{{{x = (-2 +- sqrt( 0 ))/(2)= (-b/2a) }}}
x = -1
{{{drawing(300,300, -6, 6, -6, 6,grid(1),
circle(-1, 0,0.2),
graph( 300, 300, -6, 6, -6, 6,x^2 + 2x + 1
))}}}