Answer:
The vertex is (-2,-17).
Step-by-step explanation:
We have given y=2x²+8x-9
To find the x-coordinates we use:
xv= -b/2a
where a=2 and b=8
Now put the values in the formula:
xv= -(8)/2(2)
xv=-8/4
xv= -2
Now to find the y coordinates, we will simply substitute the value in the given equation:
y=2x²+8x-9
y=2(-2)²+8(-2)-9
y=2(4)-16-9
y=8-16-9
y=-8-9
y= -17
Therefore the vertex is(-2, -17)....
