Respuesta :

Answer:

-x²+7x+18

Step-by-step explanation:

(x+2) (9-x).

x(9-x)+2(9-x)

9x-x²+ 18-2x

9x-2x-x²+18

7x-x²+18

-x²+7x+18

Answer:

x^2-7x-18

Step-by-step explanation:

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