Notăm:
AB=x, BC=y, OA=OC=OB=OD=a.
a)
[tex]\it \mathcal{P}_{ABC}=24 \Rightarrow x+2a+y=24 \Rightarrow y=24-(x+2a)\ \ \ \ \ (1)\\ \\ \mathcal{P}_{AOB}=18 \Rightarrow x+2a=18\ \ \ \ \ (2)\\ \\ (1),\ (2) \Rightarrow y=24-18 =6\Rightarrow BC=6cm[/tex]
b)
[tex]\it \mathcal{P}_{ABC}=48 \Rightarrow x+y+2a=48 \Rightarrow x= 48-(y+2a)\ \ \ \ (1)\\ \\ \mathcal{P}_{BOC}=32 \Rightarrow y+2a=32\ \ \ \ \ (2)\\ \\ (1),\ (2) \Rightarrow x=48-32=16 \Rightarrow AB=16\ cm[/tex]
