Answer:
18 units
Explanation:
a+a=6
a=3
all the a lengths are the same
so the top two triangles have legs equal to a
we use a^2 + b^2 =c^2
a and b are the legs, c is the slant
9+9=18
c= sqrt. 18
we times that by 2 since there are two
so
8.485
then the bottom two triangles
a+b=7
3+b=7
b=4
a^2 + b^2 =c^2 (use again)
c=5
times by two
10
then add all the sides
10+8.485=18.485