document.write( "Question 1155004: Solve the equation 15x^3+14x^2-3x-2=0given that -1 is a zero of f(x)15x^3+14x^2-3x-2=0\r
\n" ); document.write( "\n" ); document.write( "where does the (x+1) come from? \r
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\n" ); document.write( "\n" ); document.write( "what is the best way to solve \r
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Algebra.Com's Answer #777545 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
Solve the equation \"15x%5E3%2B14x%5E2-3x-2=0\"\r
\n" ); document.write( "\n" ); document.write( "given that \"-1\" is a zero of \"f%28x%29=15x%5E3%2B14x%5E2-3x-2=0\"\r
\n" ); document.write( "\n" ); document.write( "recall zero product theorem:\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=%28x-x%5B1%5D%29%28x-x%5B2%5D%29%28x-x%5B3%5D%29\" where \"x%5B1%5D\",\"x%5B2%5D\", and \"x%5B3%5D\" are zeros\r
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\n" ); document.write( "\n" ); document.write( "if \"x%5B1%5D=-1\" is a zero, than \"%28x-x%5B1%5D%29=x-%28-1%29=x%2B1\" \r
\n" ); document.write( "\n" ); document.write( "that is where the (x+1) comes from, and it means that \"15x%5E3%2B14x%5E2-3x-2=0\" is divisible by \"x%2B1\" or \"x%2B1\" is one of the factors \r
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\n" ); document.write( "\n" ); document.write( " the best way to solve is try to factor completely\r
\n" ); document.write( "\n" ); document.write( "since you know \"x%2B1\" is a factor, try to make groups that will factor out \"x%2B1\" \r
\n" ); document.write( "\n" ); document.write( "\"15x%5E3%2B14x%5E2-3x-2=0\"......write \"14x%5E2\" as \"-x%5E2%2B15x%5E2\" and \"-3x\" as \"-2x-x\"\r
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\n" ); document.write( "\n" ); document.write( "\"15x%5E3-x%5E2%2B15x%5E2-2x-x-2=0\"...group\r
\n" ); document.write( "\n" ); document.write( "\"%2815x%5E3%2B15x%5E2%29-%28x%5E2%2Bx%29-%282x%2B2%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"15x%5E2%28x%2B1%29-x%28x%2B1%29-2%28x%2B1%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x+%2B+1%29%2815x%5E2+-+x+-+2%29+=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x+%2B+1%29%2815x%5E2+%2B5x+-+6x+-+2%29+=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x+%2B+1%29%28%2815x%5E2+%2B5x%29+-+%286x+%2B+2%29%29+=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x+%2B+1%29%285x%283x+%2B1%29+-+2%283x+%2B+1%29%29+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x+%2B+1%29%283x+%2B+1%29%285x-2%29+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "now, find solutions\r
\n" ); document.write( "\n" ); document.write( "if \"%28x+%2B+1%29+=+0\"=>\"x=-1\"\r
\n" ); document.write( "\n" ); document.write( "\"%283x+%2B+1%29=+0\"=>\"3x=-1\"=>\"x=-1%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"%285x-2%29+=+0\"=>\"5x=2\"=>\"x=2%2F5\"\r
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