Posted by Kaitlyn on .
So... I know the answer to the question because it's something we worked on in class... but there's one part I don't get.
Factoring
m  2n + m^2  4n^2
m  2n + (m + 2n) (m  2n)
Then there's a 1...
1(m  2n) (m + 2n) (m  2n)
AND my question is...
How and why does this 1 go over here and do this from the step above?? ...
(m  2n) (1 + m + 2n)
And the answer somehow is
(m  2n) (1 + m + 2n)
m  2n + (m + 2n) (m  2n)
(m  2n) + (m + 2n) (m  2n)
This is like
a + b a
a(1+b) where a is m2n and b is m+2n

algebra 
arash,
good