Réponse :
Explications étape par étape
Bsr
FEDC = 2*4 = 8
GFCI = x*4 = 4x
HCBA = 2x * x = 2x²
GIH = (4*2x)/2 = 8x/2 = 4x
=> 8 +4x + 2x² + 4x = 2x² +8x+8
2)
x= 5
2x² +8x+8 => 50 +40 +8 = 98
x= 6
72 +48 +8 = 128
x=5 correspond mieux
3)
2x² +8x+8 =100
2x² +8x = 100-8 = 92
2(x² +4x)= 92
(x² +4x) =92/2 = 46
avec 5,07 , on arrive à 45,98
x = 5,07
2x² +8x+8 = 2*5,07² +8*5,07 +8 =
2*25,70 + 40,56 +8= 51,14 = 48,56 = 99,70cm
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