You can put this solution on YOUR website! you need everything on one side of the = sign so that it all equals zero. We then factorise ie write it as 2 things multiplied. The reason? Well, 2 things multipled that equal zero? One or the other of tem must be zero...this is how we find the solutions.
so, first, get all terms to the one side..... We then look at the -13 and the -48..we need 2 numbers that multiply to give the -48 and add to give -13. With practice you get better at this...try 16 and 3, well, -16 and +3...
now got
so we can now say that either x-16=0 or x+3=0.
Hence x=16 or x=-3.
cheers
Jon.