Respuesta :

(a)

Given data:

The given expression is x^2 -.......x +16.

The first expression can be written as,

[tex]\begin{gathered} x^2-.\ldots..x+16=x^2-2(x)(4)+(4)^2 \\ =x^2-8x+16 \\ =(x-4)^2 \end{gathered}[/tex]

Thus, the unknown value is 8.