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3 years ago

If 2x-3y=10. and xy=16 find the value of8x³-27y³

Mathematics

1 answer:

andrew11 [14]3 years ago

7 0

Answer:

8x³-27y³=3880

Step-by-step explanation:

2x-3y=10

xy=16

8x³-27y³=?

as we know that

(a-b)³=a³-b³-3ab(a-b)

now we substitue the formula according to our question

(2x-3y)³=(2x)³-(3y)³-3(2x)(3y)(2x-3y)

(10)³=8x³-27y³-18(16)(10)

1000=8x³-27y³-2880

1000+2880=8x³-27y³

3880=8x³-27y³

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Step-by-step explanation:

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