document.write( "Question 151436: How would you find 2 positive numbers that differ by 2 and have a product of 20? I dont know how to set up the equation in this instance. \n" ); document.write( "
Algebra.Com's Answer #111324 by jim_thompson5910(35256)\"\" \"About 
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\"2 positive numbers that differ by 2\" translates to \"x-y=2\" and \"have a product of 20\" translates to \"x%2Ay=20\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-y=2\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x=2%2By\" Add \"y\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2=y\" Subtract 2 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "So after isolating \"y\", we get \"y=x-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2Ay=20\" Move onto the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%2A%28x-2%29=20\" Plug in \"y=x-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x=20\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x-20=0\" Subtract 20 from both sides.\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=-2\", and \"c=-20\"\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-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-20%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=-2\", and \"c=-20\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-20%29+%29%29%2F%282%281%29%29\" Negate \"-2\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4-4%281%29%28-20%29+%29%29%2F%282%281%29%29\" Square \"-2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4--80+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-20%29\" to get \"-80\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4%2B80+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%284--80%29\" as \"sqrt%284%2B80%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+84+%29%29%2F%282%281%29%29\" Add \"4\" to \"80\" to get \"84\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+84+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+2%2Asqrt%2821%29%29%2F%282%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282%29%2F%282%29+%2B-+%282%2Asqrt%2821%29%29%2F%282%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1+%2B-+sqrt%2821%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1%2Bsqrt%2821%29\" or \"x+=+1-sqrt%2821%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the values of x are \"x+=+1%2Bsqrt%2821%29\" or \"x+=+1-sqrt%2821%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=5.583\" or \"x=-3.583\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=x-2\" Go back to the first isolated equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2Bsqrt%2821%29-2\" Plug in \"x+=+1%2Bsqrt%2821%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1%2Bsqrt%2821%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the first pair of numbers is \"x+=+1%2Bsqrt%2821%29\" and \"y=-1%2Bsqrt%2821%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=x-2\" Go back to the first isolated equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=1-sqrt%2821%29-2\" Plug in \"x+=+1-sqrt%2821%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1-sqrt%2821%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the next pair of numbers is \"x+=+1-sqrt%2821%29\" and \"y=-1-sqrt%2821%29\"
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