Answer: (4y-9z)( 16y^2 + 36yz + 81z^2 )
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Step-by-step explanation:
We'll use the difference of cubes factoring rule
a^3 - b^3 = (a-b)(a^2+ab+b^2)
In this case,
- a^3 = 64y^3 which leads to a = 4y
- b^3 = 729z^3 which leads to b = 9z
So,
a^3 - b^3 = (a-b)(a^2+ab+b^2)
64y^3 - 729z^3 = (4y-9z)( (4y)^2 + (4y)(9z) + (9z)^2 )
64y^3 - 729z^3 = (4y-9z)( 16y^2 + 36yz + 81z^2 )