Răspuns :
perimetrul=2 ori latime + 2 ori lungime
deci 140= 2*50 + 2 ori latime
2 latime= 140-100
latime= 40:2
latime =20
deci 140= 2*50 + 2 ori latime
2 latime= 140-100
latime= 40:2
latime =20