The formula to determine the perimeter of a triangle if you only know 2 sides (any 2 sides) is : A squared + b squared = c squared, where a and b represent the respective lengths of the sides you know.
The base and height are insufficient to define the perimeter.
The minimum perimeter probably corresponds to an isosceles triangle of the given base and height (with the apex above the midpoint of the base). The maximum perimeter is infinite, if the triangle is allowed to be obtuse.
The minimum perimeter probably corresponds to an isosceles triangle of the given base and height (with the apex above the midpoint of the base). The maximum perimeter is infinite, if the triangle is allowed to be obtuse.