factor each polynomial completely.27x^3-y^3
This is a "difference of cubes".
If you have a^3 - b^3, you factor it as:
(a - b)(a^2 + ab + b^2)
In this problem, a = 3x, b = y, so:
(3x-y)(9x^2 + 3xy + y^2)
Let me know if you have any questions,
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