If 3x-2y=5 and xy=6 find the value of 27xcube -8ycube
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3x - 2y = 5
Then , both side cubing.
(3x - 2y)^3 = (5)^3
27x^3 - 8y^3 - 18xy(3x - 2y) = 125
27x^3 - 8y^3 - (18*6*5) = 125
27x^3 - 8y^3 - 540 = 125
27x^3 - 8y^3 = 665
Then , both side cubing.
(3x - 2y)^3 = (5)^3
27x^3 - 8y^3 - 18xy(3x - 2y) = 125
27x^3 - 8y^3 - (18*6*5) = 125
27x^3 - 8y^3 - 540 = 125
27x^3 - 8y^3 = 665
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