Answer:
21.62m
Step-by-step explanation:
first draw the the pipe
second you need know wich is the angle between the pipe and the corner
β=Tan^-1(6/9)=33.7
find the components using tow triangles
a=9/cos(33.7)=10.81m
b=6/sen(33.7)=10.81m
finally sum the leghts
L=10.81+10.81=21.62mm
attached procedure
purple in the top left
um I don't know, it looks right, lol I'm sorry I hope this helps you let me know if its right