Question

va rog .......******​

Answer 1

Răspuns:

Explicație pas cu pas:

8a)

P = 4L

A = L*L

P1 = 4*12,5 = 50 cm

A1 = 12,5*12,5 = 156,25 cm^2

P2 = 4*10,5 = 42 cm

A2 = 10.5*10.5 = 110,25 cm^2

P1/P2 = 50/42 = 25/21

A1/A2 = 156,25/110,25 = 15625/11025 = 625/441

b)

P1 = 4*6/5 = 24/5 cm

P2 = 4*18/5 = 72/5 cm

P1/P2 = 24/5 : 72/5 = 24/5*5/72 = 24/72 = 6/18

A1 = 6/5*6/5 = 36/25

A2 = 18/5*18/5 = 324/25

A1/A2 = 36/25 : 324/25 = 36/25*25/324 = 36/324 = 1/9

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9.

L1/L2 = 7/2

P1/P2 = 4L1/4L2 = L1/L2 = 7/2

A1/A2 = L1*L1/L2*L2 = (L1/L2)*(L1/L2) = 7/2*7/2 = 49/4

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10.

L1/L2 = 8/5

l1/l2 = 4/3

A1 = L1*l1

A2 = L2*l2

A1/A2 = L1*l1/L2*l2 = (L1/L2)*(l1*l2) = 8/5*4/3 = 32/15

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11.

A1/A2 = 81/121

A1/A2 = L1*L1/L2*L2

81/121 = 9*9/11*11

L1/L2 = 9/11

P1/P2 = 4L1/4L2 = L1/L2 = 9/11