Respuesta :

Option D gives the correct answer.

Step by step solution is listed below:

[tex](7 x^{2} -4x-7)(2x+8) \\ \\ =2x(7 x^{2} -4x-7)+8(7 x^{2} -4x-7) \\ \\ =14x^{3}-8 x^{2} -14x+56 x^{2} -32x-56 \\ \\ =14 x^{3}+48 x^{2} -46x-56 [/tex]