Matematica e...

PERIMETRI E FORMULE INVERSE
Per ogni poligono calcola la dimensione mancante.
D C
P = 18 cm
b = 5 cm
h = (P : 2) – b
h = (18 : 2) – 5 = ____ 4 cm
A B
C
A B
Completa le tabelle.
Rettangolo
P = 20 cm
h = 4 cm
Triangolo
isoscele
P = 118 cm
b = 34 cm
Romboide
P = 286 m
l = 42 m
SPAZIO E FIGURE
P = 104 m
b = 40 m
l = (P – b) : 2
D C
P = 68 m
b = 20 m
l = (P : ____) 2 – ____ b
A B
l = (____ 104 – ____) 40 : 2 = 32 ____ m A B b = ______________________________
78 – (24x2) = 30 m
l = (____ 68 : ____) 2 – ____ 20 = ____ 14 m
b = (P : 2) – h
b = (___ 20:
2) – ___ 4 = ___ 6 cm
l = (P _____________________________
– b) : 2
l = (118-34) _____________________________
: 2 = 42 cm
b = (P ____________________________
: 2) – l
b = (286:2) ____________________________
– 42 = 101 cm
D C
A B
C
D C
Triangolo
isoscele
P = 47 dm
l = 12,5 dm
Romboide
P = 464 cm
l = 102 cm
Rettangolo
P = 608 m
b = 203 m
P = 22 m
h = 3 m
b = (P : 2) – h
b = (____ 22 : ____) 2 – ____ 3 = ____ 8
m
P = 78 cm
l = 24 cm
b = P – (l x 2)
P = 96 cm
l = 13 cm
b = (P : ____) 2 – ____ l
b = ______________________________
(96:2) – 13 = 35 cm
A B
b = ____________________________
P – (l x 2)
b = 47 ____________________________
– (12,5x2) = 22 dm
b = ____________________________
(P : 2) – l
b = (464:2) ____________________________
– 102 = 130 cm
h = ____________________________
(P : 2) – b
h = (608:2) ____________________________
– 203 = 101 m
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