Bethrine,
You nominate a 'Bent plate'
How is it bent ?
I assume the vertex will NOT be sharp as you have depicted. It is physically impossible to 'bend' plate with a sharp vertex.
Plate is bent with an internal radius that translates to the outside. The minimum effective radius is determined by the thickness and material.
Regarding dimensioning ..
What is the critical criteria ?
.. the horizontal distance between inside corners ?
.. the enclosed angle ?
.. the overall height ?
.. the leg distance ?
.. the internal radius ?
.. the plate length prior to bending ?
that is what you want to dimension.
added:
Regarding annotation.
The object will be symmetrical about the vertical centerline ? yes ?