document.write( "Question 172405: Find the x-intercepts. y = x2 + 3x – 10
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Algebra.Com's Answer #127303 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B3x-10=0\" Set the right side equal to zero.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=1\", \"b=3\", and \"c=-10\"\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-%283%29+%2B-+sqrt%28+%283%29%5E2-4%281%29%28-10%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=3\", and \"c=-10\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9-4%281%29%28-10%29+%29%29%2F%282%281%29%29\" Square \"3\" to get \"9\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9--40+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-10%29\" to get \"-40\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9%2B40+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%289--40%29\" as \"sqrt%289%2B40%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+49+%29%29%2F%282%281%29%29\" Add \"9\" to \"40\" to get \"49\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+49+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+7%29%2F%282%29\" Take the square root of \"49\" to get \"7\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B+7%29%2F%282%29\" or \"x+=+%28-3+-+7%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284%29%2F%282%29\" or \"x+=++%28-10%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+2\" or \"x+=+-5\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+2\" or \"x+=+-5\" \r
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\n" ); document.write( "Which means that the x-intercepts are (2,0) and (-5,0)
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