Question

What did we do in the last step http://prntscr.com/4nasbh

Answer 1

\[
\sqrt{4(9+4)} = \sqrt{4(13)} = \sqrt{4} * \sqrt{13} = 2\sqrt{13}
\]

Answer 2

Should've known. Thanks.

Answer 3

You are welcome.

Answer 4

you can actually factor the four out, add and then proceed as normal? hmmm interesting... my profs taught me to add and then break it up.