document.write( "Question 1034331: Solve the following quadratic equation by factoring (find zeroes)\r
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\n" ); document.write( "\n" ); document.write( "2x^2-2x-4=0
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Algebra.Com's Answer #648945 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "First take out the common integer factor, 2\r
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\n" ); document.write( "\n" ); document.write( "We are now looking for two binomial factors that have the following characteristics:\r
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\n" ); document.write( "\n" ); document.write( "1. The product of the constant terms is negative 2.\r
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\n" ); document.write( "\n" ); document.write( "2. The sum of the constant terms is negative 1.\r
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\n" ); document.write( "\n" ); document.write( "Since the product is negative, the two constant terms must be of opposite sign. The only two integers that have a product of 2 are 2 and 1, so we know that we are looking for either 2 times -1 or -2 times 1.\r
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\n" ); document.write( "\n" ); document.write( "Since 2 plus -1 is 1, we can discard this choice because we are looking for a sum of -1. -2 plus 1 is -1, so the two integers must be -2 and 1.\r
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\n" ); document.write( "\n" ); document.write( "That makes the two factors and \r
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\n" ); document.write( "\n" ); document.write( "Putting it all back together we get:\r
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\n" ); document.write( "\n" ); document.write( "Now you have 3 factors whose product is zero. That means one of the factors must be zero. We can eliminate 2 because 2 is not and never will be zero. That leaves and , either of which could be zero given an appropriate value for .\r
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\n" ); document.write( "\n" ); document.write( "If then \r
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\n" ); document.write( "\n" ); document.write( "If then \r
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\n" ); document.write( "\n" ); document.write( " Checks.\r
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\n" ); document.write( "\n" ); document.write( " Checks.\r
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\n" ); document.write( "My calculator said it, I believe it, that settles it\r
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