Răspuns:
a)L= l+20 A=L*l 1500= L*l |___| l
|___|__| L=l+20
l*l+20l= 900+600 => l=[tex]\sqrt{900}[/tex]=30
20l=600=> l= 30 cm
L= 30+20= 50 cm L=50 cm
b) P= 2*30+2*50= 60+100=160 m
160-2,5=157.5 cm lungimea gardului
c) Ap= 25*25= 625 m (aria casei)
1500-625=875 m liberi