Question

What equation results from completing the square and then factoring?

Answer 1

Answer:

$\large\boxed{D.\ (x-4)^2=55}$

Step-by-step explanation:

$(a-b)^2=a^2-2ab+b^2\qquad(*)\\\\\\x^2-8x=39\\\\x^2-2(x)(4)=39\qquad\text{add}\ 4^2=16\ \text{to both sides}\\\\\underbrace{x^2-2(x)(4)+4^2}_{(*)}=39+16\\\\(x-4)^2=55$