a)AB=2*5=10 cm PerimetrulABCD=4*AB=40 cm b)Tabla de joc din figura are 25 de patrate,dintre care 12 sunt albe: 12/25=48/100=48% c)AP = BQ =CM = DN , AN = BP = CQ = DM , ∢A ≡ ∢ B ≡ ∢ C≡ ∢D ∆ NAP ≡ ∆ PBQ ≡ ∆ QCM ≡ ∆MDN → NP = PQ= QM = MN → MNPQ romb → MP ⊥ NQ
