Factor 216x^3-27y^3
STEP 1: Factor out a GCF, if there's one! There's one.
STEP 2: Apply the DIFFERENCE of CUBES to the NEW binomial.
STEP 3: Whatever factors you get in Step 2, check to make sure that they are PRIME.
If so, you're done. If not, then continue factoring until the binomial is COMPLETELY factored.