Factoring polynomials

Please help factor these polynomials. I would also appreciate if you can discuss briefly how you arrived at the answer, and provide tips on how to work on similar problems in the future. Thanks 1.) x2 – 15x + 54 2.) x2 – 8x – 9 3.) x2 – 10x – 11 4) x2 – 6x – 16 Sample...