Question 89493
y=-x^2+4x-5
{{{ graph( 300, 200, -6, 5, -10, 10, y = -x^2 +4x -5) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = -x^2 +4x -5). 
the vertex is (2,-1)