document.write( "Question 924054: the pair of linear equations 3x + 7y = k, 12x + 2ky = 4k + 1 do not have any solutions if k = ? \n" ); document.write( "
Algebra.Com's Answer #560590 by MathLover1(20850)\"\" \"About 
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given:
\n" ); document.write( "the pair of linear equations
\n" ); document.write( "\"3x+%2B+7y+=+k\"
\n" ); document.write( "\"12x+%2B+2ky+=+4k+%2B+1+\"\r
\n" ); document.write( "\n" ); document.write( "find: \"k\" such that the pair of linear equations does not have any solutions\r
\n" ); document.write( "\n" ); document.write( "recall:\r
\n" ); document.write( "\n" ); document.write( "if solving a linear system, in fact there are only three possible cases:\r
\n" ); document.write( "\n" ); document.write( " No solution
\n" ); document.write( " One solution
\n" ); document.write( " Infinitely many solutions\r
\n" ); document.write( "\n" ); document.write( "When there is \"no\"\"+solution\" the equations are called \"inconsistent\" and the lines are \"parallel\"\r
\n" ); document.write( "\n" ); document.write( "One or infinitely many solutions are called \"consistent\"-overlapping lines\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "so, your lines \"must\" be parallel, and they will be parallel if they have \"same\"\"+slope\"\r
\n" ); document.write( "\n" ); document.write( "now, solve your line for \"y+\" \r
\n" ); document.write( "\n" ); document.write( "\"3x+%2B+7y+=+k\"\r
\n" ); document.write( "\n" ); document.write( "\"7y+=k-3x+\"\r
\n" ); document.write( "\n" ); document.write( "\"y+=-%283%2F7%29x+%2Bk%2F7\" => slope is \"m%5B1%5D=-%283%2F7%29\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"12x+%2B+2ky+=+4k+%2B+1+\"\r
\n" ); document.write( "\n" ); document.write( "\"2ky+=+-12x+%2B4k+%2B+1+\"\r
\n" ); document.write( "\n" ); document.write( "\"y+=+-%2812%2F2k%29x+%2B4k%2F2k+%2B+1%2F2k+\"\r
\n" ); document.write( "\n" ); document.write( "\"y+=+-%286%2Fk%29x+%2B2+%2B+1%2F2k+\"\r
\n" ); document.write( "\n" ); document.write( "=> slope is \"m%5B2%5D=++-%286%2Fk%29\"\r
\n" ); document.write( "\n" ); document.write( "now, since \"m%5B1%5D=m%5B2%5D\", we have\r
\n" ); document.write( "\n" ); document.write( "\"-%283%2F7%29=+-%286%2Fk%29\" -solve for \"k\"
\n" ); document.write( "\"-3k=+-6%2A7\" ...both sides multiply by \"-1\" \r
\n" ); document.write( "\n" ); document.write( "\"3k=42\"\r
\n" ); document.write( "\n" ); document.write( "\"k=+42+%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"k=14\"\r
\n" ); document.write( "\n" ); document.write( "then your system is:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"3x+%2B+7y+=14\"
\n" ); document.write( "\"12x+%2B+2%2A14y+=+4%2A14+%2B+1+\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"3x+%2B+7y+=14\"
\n" ); document.write( "\"12x+%2B+28y+=+57\"
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\n" ); document.write( "\n" ); document.write( "see the graph: \r
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