Question 205557
Remember  that,,,a^3 -b^3 = (a-b)(a^2 +ab+b^2)
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64y^3 -125z^3
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4^3y^3 -5^3z^3
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(4y)^3 -(5Z)^3,,,,,or  a=(4y),,,b= (5z)
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(4y-5z){ (4y)^2 + (4y)(5z) +(5z)^2 }
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(4y -5z)(16y^2 +20yz + 25 z^2)
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or  answer  (c)