Question 86782
The perimeter basically means the total length of all the surrounding sides of any object.

In this case, you have a triangle, so 3 sides.
So Perimeter (p) is simiply to add up all three sides

P=(Side#1)+(Side#2)+(Side#3)

You now need to determine what the Side#1, Side#2, and Side#3.
***It not very clear from you discription, so I could not go further****