Hey there,
You can model the entrance to a mine shaft using the equation
y = − 2 (x + 4)(x − 4), where x and y are measured in feet. The x-axis represents
the ground. Find the width of the entrance at ground level.
Based by looking on this question above, your correct answer would be . . .
[tex]\boxed{y=8}[/tex] and [tex]\boxed{x=-1}[/tex]
Hope this helps.
~Jurgen