document.write( "Question 1115736:
\n" ); document.write( "Find the value of c so that the equation will have exactly one rational solution.
\n" ); document.write( "p^2-10p+c=0
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Algebra.Com's Answer #730562 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "First I'm going to alter \"p%5E2-10p%2Bc=0\" so that it's in a more familiar form
\n" ); document.write( "p^2-10p+c=0
\n" ); document.write( "x^2-10x+c=0 ... replace every 'p' with 'x'
\n" ); document.write( "1x^2-10x+c=0 ... rewrite x^2 as 1x^2
\n" ); document.write( "1x^2+(-10)x+c=0 ... rewrite the \"1x^2-10x\" as \"1x^2+(-10)x\"\r
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\n" ); document.write( "\n" ); document.write( "Note how \"1x%5E2%2B%28-10%29x%2Bc=0\" is in the form \"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "It might be better to line up the terms like so
\n" ); document.write( "1x^2+(-10)x+c=0
\n" ); document.write( "ax^2+bx+c=0\r
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\n" ); document.write( "\n" ); document.write( "Which helps us see that
\n" ); document.write( "a = 1
\n" ); document.write( "b = -10
\n" ); document.write( "c = unknown for now\r
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\n" ); document.write( "\n" ); document.write( "Now turn to the discriminant formula
\n" ); document.write( "\"d+=+b%5E2+-+4ac\"
\n" ); document.write( "Exactly one rational solution occurs when \"d+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "So we'll plug in a = 1, b = -10, and d = 0. Then we'll solve for c
\n" ); document.write( "\"d+=+b%5E2+-+4ac\"\r
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\n" ); document.write( "\n" ); document.write( "\"0+=+%28-10%29%5E2+-+4%281%29c\"\r
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\n" ); document.write( "\n" ); document.write( "\"0+=+100-4c\"\r
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\n" ); document.write( "\n" ); document.write( "\"4c+=+100\"\r
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\n" ); document.write( "\n" ); document.write( "\"c+=+100%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"c+=+25\" (this is the final answer)\r
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\n" ); document.write( "\n" ); document.write( "So the equation \"p%5E2-10p%2Bc=0\" becomes \"p%5E2-10p%2B25=0\"\r
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\n" ); document.write( "\n" ); document.write( "I'll leave it as an exercise for you to confirm that \"p%5E2-10p%2B25=0\" has exactly one solution, and to find the solution. Though this is optional, its good to practice. Hint: Quadratic Formula
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