I was working on a homework problem today and I got stuck, so I tried manipulating the equation as many different ways as I thought possible hoping that rearranging and substitution would allow me to see something that I was not taking into account. No luck, so then I took a break as is often recommended and I am still stuck. I gave an honest attempt for about two hours. One hour before the break and one hour after it. I then did a google search and found the problem and an explanation, and I understood what I did wrong which was "factoring out a negative sign"..... When one is struggling with a homework problem should one look for the answer or work at it till one gets it?