document.write( "Question 463148: Which pair of equations does NOT have a common solution?
\n" ); document.write( "a) x+y = -1; 4x-3y=24
\n" ); document.write( "b)4x+6y=12; 6x+9y=12
\n" ); document.write( "c) 2x-3y=-4; 2x+y=4
\n" ); document.write( "d) 5x-4y=9; x-2y=-3\r
\n" ); document.write( "\n" ); document.write( "Please Explain solution\r
\n" ); document.write( "\n" ); document.write( "Thank you!
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Algebra.Com's Answer #317375 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
Which pair of equations does NOT have a common solution?
\n" ); document.write( "a) \r
\n" ); document.write( "\n" ); document.write( "\"x%2By+=+-1\"; \"4x-3y=24\"\r
\n" ); document.write( "\n" ); document.write( "b)\"4x%2B6y=12\"; \"6x%2B9y=12\"\r
\n" ); document.write( "\n" ); document.write( "c) \"2x-3y=-4\"; \"2x%2By=4\"\r
\n" ); document.write( "\n" ); document.write( "d) \"5x-4y=9\"; \"x-2y=-3\"\r
\n" ); document.write( "\n" ); document.write( "easiest way is to write all of them in slope-intercept form and see if any of them are parallel lines; parallel lines do NOT have a common solution\r
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\n" ); document.write( "\n" ); document.write( "a) \r
\n" ); document.write( "\n" ); document.write( "\"y+=-x-1\"...slope is \"-1\" \r
\n" ); document.write( "\n" ); document.write( "\"4x-24=3y\"\r
\n" ); document.write( "\n" ); document.write( "\"%284%2F3%29x-8=y\"..slope is \"%284%2F3%29\"\r
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\n" ); document.write( "\n" ); document.write( "b)\r
\n" ); document.write( "\n" ); document.write( "\"4x%2B6y=12\"...\"6y=-4x%2B12\"...\"y=-%284%2F6%29x%2B2\".\"y=-%282%2F3%29x%2B2\"...slope is \"-%282%2F3%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B9y=12\".....\"9y=-6x%2B12\"...\"y=-%286%2F9%29x%2B12%2F9\"...\"y=-%282%2F3%29x%2B4%2F3\"...slope is \"-%282%2F3%29\"\r
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\n" ); document.write( "\n" ); document.write( "c) \r
\n" ); document.write( "\n" ); document.write( "\"2x-3y=-4\" .....\"2x%2B4=3y\" .....\"%282%2F3%29x%2B4%2F3=y\" ...slope is \"%282%2F3%29\"\r
\n" ); document.write( "\n" ); document.write( "\"2x%2By=4\"...\"y=-2x%2B4\"...slope is \"-2\"\r
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\n" ); document.write( "\n" ); document.write( "d)
\n" ); document.write( "\"5x-4y=9\"....\"5x-9=4y\"...\"%285%2F4%29x-9%2F4=y\"..slope is \"%285%2F4%29\"\r
\n" ); document.write( "\n" ); document.write( " \"x-2y=-3\".....\"x%2B3=2y\".....\"%281%2F2%29x%2B3%2F2=y\".slope is \"%281%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "as you can see, only \r
\n" ); document.write( "\n" ); document.write( "b)\r
\n" ); document.write( "\n" ); document.write( "\"4x%2B6y=12\" and \"6x%2B9y=12\" have same slope..\r
\n" ); document.write( "\n" ); document.write( "let's see if these lines are parallel:\r
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\n" ); document.write( "\n" ); document.write( "so, your answer is \"b\"
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