Perimeter of a trapezoid

From  the top right vertex,  draw  a line parallel to  the  base......the length of  this line segment  inside the trapezoid = 24

So  this froms  a   7  - 24  - 25    right triangle   at  the top of the trapezoid

So....the perimeter   =

7  + 13  + 24  + 13  + 25  =  

82