Question

Помогите пожалуйста! Буду очень благодарна!

Answer 1

7)
$\left \{ {{2x \leq -6} \atop {x \geq -6}} \right.$
$\left \{ {x \leq -2} \atop {x \geq -6}} \right.$
[-6; -2]
наибольшее значение -2

8)
4(4xy - (-2x - y)²) = 4(4xy + (2x+y)²) = 4(4xy + 4x² + 4xy + y²) = 32xy + 16x² + 4y² = 32√15 + 16*5 + 4*3 = 92 + 32√15

9)
(a+b+c)y = ab
ab - ay = by + cy
a(b-y) = y(b+c)
a = (y(b+c))/(b-y)
a = 1,2(7,2 + 7,8)/7,2 - 1,2
a = 1,2*15/6
a = 3

Answer 2

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