8 / ( X + 4 ) + 16 / ( X - 4 ) = 4/3
24*( X - 4) + 48*( X + 4) = 4*(X^2 - 16)
24X - 96 + 48X + 192 = 4X^2 - 64
4X^2 - 72X - 160 = 0
4 * ( X^2 - 18X - 40) = 0
D = 324 + 160 = 484 ; √ D = 22
X1 = ( 18 + 22) : 2 = 20
X2 = ( - 4) : 2 = ( - 2 )
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X^2 - 16 ≠ 0
X^2 ≠ 16
X ≠ 4
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Ответ 20 км/час
https://ru-static.z-dn.net/files/d98/952931b46b8008ac7bbd695a34562fa1.jpg
18 / x - 46 / ( x - 35 ) = 1
x ≠ 0 ; x ≠ 35
(18( x - 35 ) - 46x ) / (x( x - 35 )) = 1
18x - 630 - 46x = x^2 - 35x
- 28x - 630 = x^2 - 35x
x^2 - 7x + 630 = 0
D = 49 - 2520 = - 2471 ( < 0 )
Ответ нет решений
2y-1
2y=1
y=1:2
y=0,5
Ответ: 0,5
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