What is a real world application of polynomial factoring? The wife and I are sitting here on a Saturday night doing some algebra homework.  We're factoring polynomials and had the same thought at the same time: when will we use this?
I feel a bit silly because it always bugged me when people asked that in grade school.  However, we're both working professionals (I'm a programmer, she's a photographer) and I can't recall ever considering polynomial factoring as a solution to the problem I was solving.
Are there real world applications where factoring polynomials leads to  solutions? or is it a stepping-stone math that will open my mind to more elaborate solutions that I actually will use?
Thanks for taking the time!

Ever since middle school, I used to wonder about 'real-life' applications of algebra in general; except using them for groceries.
My professor once answered the question brilliantly. Ever since, the constant bugging of this question has faded massively.
"When imaginary numbers were acknowledged, no one ever thought that complex numbers would be fundamental in electricity!"
Furthermore, I could argue that when graph theory was discovered, no one every thought that it would have strides in social sciences and criminology. Examples abound.
As mathematicians, we accumulate our knowledge in our field to draw a logical and cohesive conclusion/result that might prove to be extremely useful to humanity. :)
