Respuesta :

Answer:

7x^2 -12x(sqrt 14) + 72

Step-by-step explanation:

Use foil and you get

x^2(7) - (3x(sqrt56))+(-3x(sqrt56))+ 9(8)

= The inner terms simplify to -6x(sqrt14) + (-6x(sqrt14)) = -12x(sqrt14)

so answer is

7x^2 -12x(sqrt 14) + 72