Répondre :
a)
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| | 2m
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x
b)
L = 2*x + 2*2
L = 2x + 4
L = 2(x+2)
c)
A = x * 2
A = 2x
d)
A = 2x
6,5 = 2x
x = 6,5/2 = 65/20 = 3,25 m
L = 2(x+2) = 2( 65/20 + 2) = 2( 65/20 + 40/20) = 2(105/20) = 10,5 m
En espérant t'avoir aidé.