0:00:00.012,0:00:04.447
Try factoring these four terms. Notice that the first two terms are positive,
0:00:04.447,0:00:08.909
but the second two terms are negative. This means that for these two terms, you
0:00:08.909,0:00:13.497
should have a negative greatest common factor. Try using our same approach, and
0:00:13.497,0:00:17.933
just be careful with the negative sign. Factor this expression and write your
0:00:17.933,0:00:18.711
answer here.