Question

factoring by grouping
I am getting into this and I am lost especially when there are only letters like this one
ac - bc + ad -bd how to solve ??

Answer 1

first you want to group them with like terms.. so in what terms are common?

Answer 2

c's and d's??

Answer 3

you lost me at the very last two lines .. so u select the coomon one which is a-b and add the letters outside to the 2nd part ?

Answer 4

actually if you multiply (a-b)(c-d) you get ac-bc-ad+bd which is different from the original problem whcih was ac-bc+ad-bd

try doing it this way, put the a's and the b's together so you get (ac +ad) + (-bc-bd) so then you factor out a from the first to get a(c+d) and factor out -b from the second to get -b(c+d), putting that together you get:
a(c+d)-b(c+d), which means you can put the a and - b together to get:
(a-b)(c+d), try multiplying this out to see if you get the correct answer