Question 553819
You are close!!  


{{{(-4+-sqrt(8))/2}}}
{{{(-4+-sqrt(4)*sqrt(2))/2}}}
{{{(-4+-2*sqrt(2))/2}}}


Factor the 2 in the numerator:
{{{ (2(-2+-sqrt(2)))/2}}}


Divide out the 2, and you will have the correct answer!!
{{{-2+-sqrt(2) }}}


You may want to see my FREE website for additional explanation on this topic.  The easiest way to find the website is to use the easy-to-remember and easy-to-spell link www.mathinlivingcolor.com.  Near the bottom of this page is a link that takes you to my Homepage.  On my Homepage, look for the link "Basic, Intermediate, and College Algebra: One Step at a Time."  Choose "Basic Algebra" and look in Chapter 5 for the section on Reducing Fractions with Radicals.  There is also an explanation in "Intermediate Algebra", "Chapter 3."  I think you will really like the "Math in Living Color" pages that go with these sections.  


If you need to contact me, send me an Email at rapaljer@seminolestate.edu.


Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus