4(8-x)
4(8-x)
4 : x = 17 : (8 - x)
permuto i medi
4 : 17 = x : (8 - x)
(8 - x) : x = 17 : 4
(8 - x + x ) : x = (17 + 4) : 4
8 : x = 21 : 4
x = 8*4/21 = 32/21
4 : x = 17 : (8 - x)
32 - 4x = 17x
32 = 21x
x = 32 / 21
4 : x = 17 :(8-x)
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$\small 4 : x = 17 : (8-x)$ permuta come segue:
$\small (8-x) : x = 17 : 4$ applica il comporre:
$\small (8-\cancel{x}+\cancel{x}) : x = (17+4) : 4$
$\small 8 : x = 21 : 4$
$\small x= \dfrac{8×4}{21}$
$\small x= \dfrac{32}{21}$