document.write( "Question 140321: Solve by substitution \r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2By%5E2=26\"
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Algebra.Com's Answer #102189 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given equations\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2By%5E2=26\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B%28-x%2B8%29%5E2=26\" Plug in \"y=-x%2B8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx%5E2-16x%2B64=26\" Foil\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx%5E2-16x%2B64-26=0\" Subtract 26 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-16x%2B38=0\" Combine like terms\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( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"2%2Ax%5E2-16%2Ax%2B38=0\" ( notice \"a=2\", \"b=-16\", and \"c=38\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--16+%2B-+sqrt%28+%28-16%29%5E2-4%2A2%2A38+%29%29%2F%282%2A2%29\" Plug in a=2, b=-16, and c=38\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+%28-16%29%5E2-4%2A2%2A38+%29%29%2F%282%2A2%29\" Negate -16 to get 16\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+256-4%2A2%2A38+%29%29%2F%282%2A2%29\" Square -16 to get 256 (note: remember when you square -16, you must square the negative as well. This is because \"%28-16%29%5E2=-16%2A-16=256\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+256%2B-304+%29%29%2F%282%2A2%29\" Multiply \"-4%2A38%2A2\" to get \"-304\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+-48+%29%29%2F%282%2A2%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+4%2Ai%2Asqrt%283%29%29%2F%282%2A2%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+4%2Ai%2Asqrt%283%29%29%2F%284%29\" Multiply 2 and 2 to get 4\r
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\n" ); document.write( "\n" ); document.write( "After simplifying, the quadratic has roots of\r
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\n" ); document.write( "\n" ); document.write( "\"x=4+%2B+sqrt%283%29i\" or \"x=4+-+sqrt%283%29i\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "Since we get a complex solution for the equation \"2x%5E2-16x%2B38=0\", this means that the equations \"x%5E2%2By%5E2=26\" and \"y=-x%2B8\" do not intersect. So there are no solutions
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