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4 years ago

When x=-2 and y=-1,-x^2-5xy+5y^3 is

Mathematics

1 answer:

kirill115 [55]4 years ago

5 0

Answer:

-19

Step-by-step explanation:

Evaluate -x^2 - 5 x y + 5 y^3 where x = -2 and y = -1:

-x^2 - 5 x y + 5 y^3 = -(-2)^2 - -2 (-5) + (-1)^3×5

(-2)^2 = 4:

-4 - -5 (-2) + 5×(-1)^3

(-1)^3 = -1:

-4 - -5 (-2) + 5×-1

-5 (-2) = 10:

-4 - 10 - 5

-4 - 10 - 5 = -(4 + 10 + 5):

-(4 + 10 + 5)

| 1 | 0

| | 5

+ | | 4

| 1 | 9:

Answer: -19

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Answer:

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Step-by-step explanation:

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3 years ago

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