Respuesta :

uxleumas

Answer:

7,24,20

Step-by-step explanation:

The perimeter is simply the lengths of the sides, added up
n+4n-4+4n-8=9n-12=51 cm
9n=51+12
9n=63
n=7

plug in 7 for n to get:
7,4*7-4,4*7-8
or
7,24,20