Formulario Geometria Piana

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AREA E PERIMETRO DI FIGURE PIANE

TRIANGOLO

PERIMETRO 2p AREA A 2p = AB + BC + CD 2p = b + l1+ l2 A = AB × CH 2 AB = A × 2 CH CH = A × 2 AB A = b × h 2 b = A × 2 h h = A × 2 b

PARALLELOGRAMMA

PERIMETRO 2p AREA A 2p = AB + BC + CD + DA = 2 × AB + 2 × BC = 2 × (AB + BC) 2p = b + l + b + l = 2 × b + 2 × l = 2 × (b + l) A = AB × DH AB = A DH DH = A AB A = b × h b = A h h = A b

RETTANGOLO

PERIMETRO 2p AREA A 2p = AB + BC + CD + DA = 2 × AB + 2 × BC = 2 × (AB + BC) 2p = b + h + b + h = 2 × b + 2 × h = 2 × (b + h) A = AB × BC AB = A BC BC = A AB A = b × h b = A h h = A b

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ROMBO

PERIMETRO 2p AREA A 2p = AB + BC + CD + DA = 4 × AB AB = 2p : 4 2p = l + l + l + l = 4 × l l = 2p : 4 A = AC × BD 2 AC = A × 2 BD BD = A × 2 AC A = D × d 2 D = A × 2 d d = A × 2 D oppure il rombo `e un parallelogramma A = CB × DH CB = A DH DH = A CB A = l × h l = A h h = A l

QUADRATO

PERIMETRO 2p AREA A 2p = AB + BC + CD + DA = 4 × AB AB = 2p : 4 2p = l + l + l + l = 4 × l l = 2p : 4 A = AB × AB = AB2 AB =√A A = l × l = l2 l =√A oppure il quadrato `e un rombo A = BD × BD 2 = BD2 2 BD = √ A × 2 A = d × d 2 = d2 2 d = √ A × 2

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TRAPEZIO

PERIMETRO 2p AREA A 2p = AB + BC + CD + DA 2p = B + l1+ b + l2 A = (AB + CD) × DH 2 AB + CD = A × 2 DH DH = A × 2 AB + CD AB = A × 2 DH − CD CD = A × 2 DH − AB A = (B + b) × h 2 B + b = A × 2 h h = A × 2 B + b B = A × 2 h − b b = A × 2 h − B