document.write( "Question 148495: Solve the following equations:\r
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Algebra.Com's Answer #108821 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
a)\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-4x=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%28x%5E2-4%29=0\" Factor out the GCF x\r
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\n" ); document.write( "\n" ); document.write( "\"x%28x%2B2%29%28x-2%29=0\" Factor \"x%5E2-4\" to get \"%28x%2B2%29%28x-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"x=0\", \"x%2B2=0\" or \"x-2=0\"\r
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\n" ); document.write( "\n" ); document.write( "Now solve for x for each factor:\r
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\n" ); document.write( "\n" ); document.write( "\"x=0\", \"x=-2\" or \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "So the solutions of \"x%5E3-4x=0\" are \"x=0\", \"x=-2\" or \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2%2B7x-15=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%287%29+%2B-+sqrt%28+%287%29%5E2-4%282%29%28-15%29+%29%29%2F%282%282%29%29\" Plug in \"a=2\", \"b=7\", and \"c=-15\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49-4%282%29%28-15%29+%29%29%2F%282%282%29%29\" Square \"7\" to get \"49\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49--120+%29%29%2F%282%282%29%29\" Multiply \"4%282%29%28-15%29\" to get \"-120\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49%2B120+%29%29%2F%282%282%29%29\" Rewrite \"sqrt%2849--120%29\" as \"sqrt%2849%2B120%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+169+%29%29%2F%282%282%29%29\" Add \"49\" to \"120\" to get \"169\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+169+%29%29%2F%284%29\" Multiply \"2\" and \"2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+13%29%2F%284%29\" Take the square root of \"169\" to get \"13\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B+13%29%2F%284%29\" or \"x+=+%28-7+-+13%29%2F%284%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%286%29%2F%284%29\" or \"x+=++%28-20%29%2F%284%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+3%2F2\" or \"x+=+-5\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So our answers are \"x+=+3%2F2\" or \"x+=+-5\" \r
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