Question

find the zeros of y=x^2 +9x+8,then use the zeros to find the vertex of the graph of the parabola

Answer 1

x^2 +9x +8
= (x+8) * (x+1)
hence zeroes at -1 &-8
hence vertex at -9/2 (mean of the 2 zeroes

Answer 2

(x+8)(x+1)=0
-8,-1
the x=coordinate of the vertex is in the middle, -4.5
y-coordinate is -12.25 by substituting -4.5 in for x
(-4.5,-12.25)