If you are graphing quadratic equations of the type
ax^2 + bx + c = 0
The equation will look like a "U" <span>if "a" is positive </span>or it will look like an upside-down "U" <span>if "a" is negative </span>
I would say that the angle would be an
exterior angle because it's usually between the side of the polygon connected by a line as an extension of the adjacent side.
here's an example. hope it helps!