document.write( "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 ?\r
\n" ); document.write( "\n" ); document.write( "The actual question is this: If x = –1 and y = 2, what is the value of the expression 2x^3 – 3xy?\r
\n" ); document.write( "\n" ); document.write( "I know the answer is 4. But I don't know HOW to get there. \n" ); document.write( "

Algebra.Com's Answer #105145 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"2x%5E3-3xy\"$ Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( " $\"2%28-1%29%5E3-3%28-1%29%282%29\"$ Plug in $\"x=-1\"$ and $\"y=2\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"2%28-1%29-3%28-1%29%282%29\"$ Cube -1 to get -1\r
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\n" ); document.write( "\n" ); document.write( " $\"-2-3%28-1%29%282%29\"$ Multiply 2 and -1 to get -2\r
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\n" ); document.write( "\n" ); document.write( " $\"-2-3%28-2%29\"$ Multiply -1 and 2 to get -2\r
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\n" ); document.write( "\n" ); document.write( " $\"-2%2B6\"$ Multiply -3 and -3 to get +6\r
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\n" ); document.write( "\n" ); document.write( " $\"4\"$ Add -2 and 6 to get 4\r
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\n" ); document.write( "\n" ); document.write( "So $\"2x%5E3-3xy=4\"$ when $\"x=-1\"$ and $\"y=2\"$ \n" ); document.write( "

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