Question 609154
  <pre><font face = "Tohoma Ital" size = 3 color = "indigo"><b> 
Hi
Using the vertex form of a parabola, {{{y=a(x-h)^2 +k}}} where(h,k) is the vertex
 y = 2x^2 - 8x - 1     ||Note the use of ^(uppercase 6) to signify the exponent
 y = 2(x-2)^2 - 8 - 1  || completing the Square
 y = 2(x-2)^2 - 9      || V(2,-9)min, a = 2>0, Parabola opens Upward, Range is y&#8805; -9, domain x is (&#8722;&#8734;,&#8734;)
{{{drawing(300,300,-10,10,-10,10 ,blue(line(2,10,2,-10))   ,grid(1),
circle(2, -9,0.3),graph(300,300,-10,10,-10,10, 0,2x^2 - 8x - 1   ))}}}