2/3 * ( 10 - C ) = - 8
2/3 * ( 10 - C ) = - 24 / 3
2 * ( 10 - C ) = - 24
20 - 2C = - 24
44 = 2C
C = 22
3<a<4
5<b<6
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8<a+b<10
16<2(a+b)<20
5x+4 + 2*
+ 2x - 1 =3x+1
2*
= 6-4x
4 (5x-4)(2x-1) = 36 - 48x + 16x²
40x² - 20x - 32x + 16 - 36 + 48x - 16x² = 0
24x² - 4x - 20 = 0
6x² - x - 5 =0
6 - 1 -5=0
x₁ = 1
x₂ = -5/6 не удов., т.к. 5x-1≥0
Ответ: 1
3х+7х больше 5х
-у больше у-1
2х-3у меньше у-х