Verified answer

16) y = - x² + 5x + 5

Если x = 2 , то  y = - 2² + 5 * 2 + 5 = - 4 + 10 + 5 = 11

x + y = 2 + 11 = 13

           +                               -                             +

____________[- 3]___________[0,5]_____________

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________________________________________[2]_____

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Ответ : x ∈ (- ∞ ; - 3] ∪ [0,5 ; 2]