If the vertices of / are b(–3, 3), c(3, 5), and d(–1, 0), what is the perimeter

Considering this is a triangle you just need to take the distance from each point.

B to C ,  X ,-3 -3 = -6    Y,  3  -5 = -2    = -6,2  =-6² + 2²  = 36 + 4 = √40  Distance from B to C
C  to D , 3 - -1 = 4 , 5 - 0 = 5 , => 16 + 25 = √41

D to B , -1 --3 = -2, 0 - -3 = 3 , = > 4 + 9 = √13

Perimete = √40   + √41  +√13

The method to find the female dormitory is 2-d=800