document.write( "Question 1126098: For what values of m has the equation x^2 - 2mx +8m -15 =0
\n" ); document.write( "a) one root?
\n" ); document.write( "b) no roots?
\n" ); document.write( "c) two roots?
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Algebra.Com's Answer #742410 by MathLover1(20850)\"\" \"About 
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\"x%5E2+-+2mx+%2B8m+-15+=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2mx+%2B8m+-15+=0\"..-> compare to \"ax%5E2%2Bbx%2Bc=0\" and you see that \r
\n" ); document.write( "\n" ); document.write( "\"a=1\", \"b=2m\", and \"c=8m-15\"\r
\n" ); document.write( "\n" ); document.write( "use discriminant to find for what values of m has the equation will have certain number of solutions\r
\n" ); document.write( "\n" ); document.write( "discriminant is \"b%5E-4ac\" (portion of the quadratic formula \"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( "a) one root?\r
\n" ); document.write( "\n" ); document.write( "if \"b%5E2-4ac=0\" there is exactly one root\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2-4ac=0\"....plug in \"a=1\", \"b=2m\", and \"c=8m-15\"\r
\n" ); document.write( "\n" ); document.write( "\"%282m%29%5E2%26%238722%3B4%2A1%288m-15%29=0\"
\n" ); document.write( "\"4m%5E2-32m%2B60=0\"...simpliy
\n" ); document.write( "\"m%5E2-8m%2B15=0\".
\n" ); document.write( "\"%28m+-+5%29+%28m+-+3%29+=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"m+=+5\" or \"m+=+3\"\r
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\n" ); document.write( "\n" ); document.write( "check:\"m+=+5\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2%2A5x+%2B8%2A5+-15+=0\"
\n" ); document.write( "\"x%5E2+-+10x+%2B40+-15+=0\"
\n" ); document.write( "\"x%5E2+-+10x+%2B25+=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2Cx%5E2+-+10x+%2B25%29+\"\r
\n" ); document.write( "\n" ); document.write( "check:\"m+=+3\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2%2A3x+%2B8%2A3+-15+=0\"
\n" ); document.write( "\"x%5E2+-+6x+%2B24+-15+=0\"
\n" ); document.write( "\"x%5E2+-+6x+%2B9+=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2Cx%5E2+-+6x+%2B9%29+\"\r
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\n" ); document.write( "\n" ); document.write( "b) no roots?\r
\n" ); document.write( "\n" ); document.write( "if \"b%5E2-4ac%3C0\" there are no Real roots\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2-4ac%3C0\"....plug in \"a=1\", \"b=2m\", and \"c=8m-15\"\r
\n" ); document.write( "\n" ); document.write( "\"%282m%29%5E2-4%2A1%288m-15%29%3C0\"
\n" ); document.write( "\"4m%5E2-32m%2B60%3C0\"
\n" ); document.write( "\"%28m+-+5%29+%28m+-+3%29+%3C+0\"
\n" ); document.write( "\"m+%3C+5\" or \"m+%3E+3\"\r
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\n" ); document.write( "\n" ); document.write( "check: if \"m+%3C+5\", let say \"m+=+4\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2%2A4x+%2B8%2A4+-15+=0\"
\n" ); document.write( "\"x%5E2+-+8x+%2B32+-15+=0\"
\n" ); document.write( "\"x%5E2+-+8x+%2B17+=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2Cx%5E2+-+8x+%2B17%29+\"\r
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\n" ); document.write( "\n" ); document.write( "check:if \"m+%3E+3\", let say \"m+=3.5\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2%2A3.5x+%2B8%2A3.5+-15+=0\"
\n" ); document.write( "\"x%5E2+-+7x+%2B28+-15+=0\"
\n" ); document.write( "\"x%5E2+-+7x+%2B13+=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2Cx%5E2+-+7x+%2B13+%29+\"\r
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\n" ); document.write( "\n" ); document.write( "c) two roots? \r
\n" ); document.write( "\n" ); document.write( "if \"b%5E2-4ac%3E0\" there are two roots\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2-4ac%3C0\"....plug in \"a=1\", \"b=2m\", and \"c=8m-15\"\r
\n" ); document.write( "\n" ); document.write( "\"%282m%29%5E2-4%2A1%288m-15%29%3E0\"
\n" ); document.write( "\"4m%5E2-32m%2B60%3E0\"
\n" ); document.write( "\"%28m+-+5%29+%28m+-+3%29+%3E0\"\r
\n" ); document.write( "\n" ); document.write( "\"m+%3E+5\" or \"m+%3C+3\"\r
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\n" ); document.write( "\n" ); document.write( "check: if \"m+%3E+5\", let say \"m+=+6\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2%2A6x+%2B8%2A6+-15+=0\"
\n" ); document.write( "\"x%5E2+-+12x+%2B48+-15+=0\"
\n" ); document.write( "\"x%5E2+-+12x+%2B33+=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2Cx%5E2+-+12x+%2B33%29+\"\r
\n" ); document.write( "\n" ); document.write( "check:if \"m+%3C+3\", let say \"m+=+2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+2%2A2x+%2B8%2A2+-15+=0\"
\n" ); document.write( "\"x%5E2+-+4x+%2B16+-15+=0\"
\n" ); document.write( "\"x%5E2+-+4x+%2B1+=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2Cx%5E2+-+4x+%2B1%29+\"\r
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