SOLUTION: You answered this question wrong, because the poster wrote it wrong: If x = –1 and y = 2, what is the value of the expression 2x3 – 3xy ? The actual question is this

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Question 144397: You answered this question wrong, because the poster wrote it wrong: If x = –1 and y = 2, what is the value of the expression 2x3 – 3xy ?
The actual question is this: If x = –1 and y = 2, what is the value of the expression 2x^3 – 3xy?
I know the answer is 4. But I don't know HOW to get there.
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
Start with the given expression


Plug in and


Cube -1 to get -1


Multiply 2 and -1 to get -2


Multiply -1 and 2 to get -2


Multiply -3 and -3 to get +6


Add -2 and 6 to get 4



So when and
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