find the value of 27x^3+8y^3 if 3x+ 2y=14 and xy=8
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27x^3+8y^3=???
3x+2y=14
xy =8
so
(3x+2y)^2= 3x^2+2×3x×2y+2y^2
(14)^2 = 3x^2+ 12×8+2y^2
196 -96 =3x^2+2y^2
100=3x^2+ 2y^2
now
27x^3+8y^3 = (3x+2y ) (3x^2-6 xy +2y^2)
= 14 × 100 - 6×8
= 14 × 52
27 x^3+8y^3= 728
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3x+2y=14
xy =8
so
(3x+2y)^2= 3x^2+2×3x×2y+2y^2
(14)^2 = 3x^2+ 12×8+2y^2
196 -96 =3x^2+2y^2
100=3x^2+ 2y^2
now
27x^3+8y^3 = (3x+2y ) (3x^2-6 xy +2y^2)
= 14 × 100 - 6×8
= 14 × 52
27 x^3+8y^3= 728
plz mark me as brainiest
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