document.write( "Question 1085175: Find k such that the equation 2x^2 +kx + 8 = 0 has two equal real roots, two distinct real roots and no real roots \n" ); document.write( "

Algebra.Com's Answer #699213 by MathLover1(20849) $\"\"$ $\"About$

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\n" ); document.write( " $\"2x%5E2+%2Bkx+%2B+8+=+0+\"$ -> $\"a=2\"$ , $\"b=k\"$ , and $\"+c=8\"$ \r
\n" ); document.write( "\n" ); document.write( "if the discriminant $\"b%5E2-4ac%3E0\"$ , the equation has two distinct real roots\r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2-4%2A2%2A8%3E0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2-64%3E0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2%3E64\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%3Esqrt%2864%29\"$
\n" ); document.write( " $\"k%3E8\"$ \r
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\n" ); document.write( "\n" ); document.write( "so, we can try $\"k=9\"$ which is greater than $\"8\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"2x%5E2+%2B9x+%2B+8+=+0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+2x%5E2+%2B9x+%2B+8+%29+\"$ \r
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\n" ); document.write( "\n" ); document.write( "if the discriminant $\"+b%5E2-4ac=0\"$ , the equation has two equal real roots\r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2-4%2A2%2A8=0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2-64=0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2=64\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k=sqrt%2864%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k=8\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C++2x%5E2+%2B8x+%2B+8%29+\"$ \r
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\n" ); document.write( "\n" ); document.write( "if the discriminant $\"b%5E2-4ac%3C0\"$ , there are no real solutions\r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2-4%2A2%2A8%3C0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2-64%3C0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%5E2%3C64\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"k%3Csqrt%2864%29\"$
\n" ); document.write( " $\"k%3C8\"$ \r
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\n" ); document.write( "\n" ); document.write( "if $\"k=7\"$ ->\r
\n" ); document.write( "\n" ); document.write( " $\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C++2x%5E2+%2B7x+%2B+8%29+\"$
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