They want you to factor using the AC method. If you are familiar with this, it means to label the coefficients.
In this case A=1 B=8 and C=16
Now, multiply A times C and you get 16
Now, what are two numbers that multiply to give you 16 that also add up to 8?
I hope you're thinking 4!! 4+4=8 and 4*4=16
This means that 4 is a factor so you can rewrite [tex]w^{2}+8w+16 [/tex] as [tex](w+4)(w+4) [/tex]