Question

What value completes the square for the expression x^2+16x

64
8
-64
-8

Answer 1

You have the expression x^2+16x. Then, to find the value that completes the square for it, you must apply the following proccedure:

x^2+16x=0
x^2+16x+0=0

This quadratic equation needs to have the following form:

a(x+d)^2+e

Then, you have:

(b/2)^2=(16/2)^2=(8)^2=64

Therefore, the expression is:

x^2+16x+64=64
(x+8)^2=64

The answer is the first option= 64