Answer:
This may be a function of the absolte value family.
f(x) = IxI.
f(x) = x if x ≥ 0
f(x) = -x if x ≤ 0
Where this is the parent function, and the graph is shown below in green.
If the coefficient is positive, then the lines open upwards, and we will have a minimum (in this case, when x = 0).
And also in this case, we have symmetry around the value x = 0.
Now, the vertex can also be an absolute maximum if the coefficient is negative, like in the example shown below in color blue (the equation for the blue graph is f(x) = -3*IxI )