I think you might need Desmos for graphing?? Explain your answer!

Yes you are correct! This equation will make a parabola. The width when the arch is at ground level would be the x-intercepts, or zeros, of the parabola.
The vertex point is (0,12)
the axis of symmetry is 0
The zeros are (-4,0) and (4,0)
using the zeros take away the negative because something cant be negative feet wide and add the numbers together (4+4)
Your answer is 8
i attached the graph
Hope this helps you!
P.S. Can i get brainliest? :)