Răspuns :
1.)P=4l=4.2,5=>P=10cm, A=l,la a doua=2,5*2,5=>A=6,25 cm patrati.
1)a=2.5cm ,P=4a=2.5*4=10cm
2)p=2a+2b=8+0.7=8.7
A=a*b=4*0.35=1.4cm2