document.write( "Question 328671: Find the value(s) of k so that 3/4 x^2 + kx = -27 has one real rational root. \n" ); document.write( "

Algebra.Com's Answer #235516 by Fombitz(32388) $\"\"$ $\"About$

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Use the discriminant, D.
\n" ); document.write( " $\"D=b%5E2-4ac\"$
\n" ); document.write( "When D=0, the quadratic has one real rational (double) root.
\n" ); document.write( " $\"%283%2F4%29x%5E2%2Bkx%2B27=0\"$
\n" ); document.write( " $\"D=k%5E2-4%283%2F4%29%2827%29=0\"$
\n" ); document.write( " $\"k%5E2-81=0\"$
\n" ); document.write( " $\"k=0+%2B-+9\"$
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\n" ); document.write( "Both instances of k are shown in the graph (+9-Red,-9 Green).
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