Answer:
It is called the vertex
Step-by-step explanation:
Every parabola has a shape of an U, then, they have an extreme point. Depending if the parabola has the formula y = ax^2 + bx + c or x = ay^2 + by + c (where a, b and c are constants) and what value constant a has, what kind of extreme point the parabola have.
There are four cases:
y = ax^2 + bx + c with a>0 -> the extreme point is the lowest point
y = ax^2 + bx + c with a<0 -> the extreme point is the highest point
x = ay^2 + by + c with a>0 -> the extreme point is the farthest point left
x = ay^2 + by + c with a<0 -> the extreme point is the farthest point right
