Respuesta :

just add up the lengths of the three sides

length of AB =

[tex] \sqrt{ {2}^{2} + {6}^{2} } [/tex]

length of BC

[tex] \sqrt{ {7}^{2} + {3}^{2} } [/tex]

length of CA

[tex] \sqrt{ {5 }^{2} + {1}^{2} } [/tex]

(yeah, it's with pythagoras)

let's sum everything up

length AB+BC+CA = 21.011

the units would just be considered as "length units" I guess

hope it helps. have a nice day.

feel free to ask questions.

and maybe, if I'm feeling really nice and a lil bored, i leave greeting answers under yours to enable posters to give gives brainliests. if theres no 2and answer at least