Answer:
37.7cm
Step-by-step explanation:
Rly depends on your relationship with him tho. If you guys are in a relationship, maybe he wants to prove that he has no secret and you can open his phone and go through his dms or something? If not, maybe he just wants someone to hold his phone for him. Either way, don't overthink. Hope this helps!
Perimeter = 72 m
Side length = 18 m
Error checking:
18 + 18 + 18 + 18 = 72 m
Both the angles will be 105°
Just add up the given angles, subtract the result by 360, and divide by 2.