document.write( "Question 1152631: Which of the following equations would not be consistent with 3y - 4x = 7?
\n" ); document.write( "A. - 8x = 6y - 14
\n" ); document.write( "B. 12y = - 9x + 28
\n" ); document.write( "C. - 16x + 28 = 12y
\n" ); document.write( "D. - 4x - 3y - 7 = 0
\n" ); document.write( "E. - 56 - 24y = - 32x \n" ); document.write( "

Algebra.Com's Answer #774684 by Edwin McCravy(20065) $\"\"$ $\"About$

You can put this solution on YOUR website!
Which of the following equations would not be consistent with 3y - 4x = 7?
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document.write( "Find two points on the line which has that equation:\r\n" );
document.write( "Let y=1, then\r\n" );
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document.write( "  3y - 4x = 7\r\n" );
document.write( "3(1) - 4x = 7\r\n" );
document.write( "   3 - 4x = 7\r\n" );
document.write( "      -4x = 4\r\n" );
document.write( "        x = -1, so (1,-1) is one point on the line whose equation is 3y - 4x = 7  \r\n" );
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document.write( "Let x=2, then\r\n" );
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document.write( "  3y - 4x = 7\r\n" );
document.write( "3y - 4(2) = 7\r\n" );
document.write( "   3y - 8 = 7\r\n" );
document.write( "       3y = 15\r\n" );
document.write( "        y = 5, so (2,5) is another point on the line whose equation is 3y - 4x = 7\r\n" );
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document.write( "Let's substitute (1,-1) and (2,5) in each of those.  If they both satisfy the\r\n" );
document.write( "equation, the equation is compatible with 3y - 4x = 7.  But if either one of\r\n" );
document.write( "the two points does not, then the equation is not compatible with 3y - 4x = 7.\r\n" );
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A. - 8x = 6y - 14

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document.write( "Substituting (1,-1)\r\n" );
document.write( "-8x = 6y - 14\r\n" );
document.write( "-8(1) = 6(-1) - 14\r\n" );
document.write( "   -8 = -6 - 14\r\n" );
document.write( "   -8 = -20     [So (1,-1) DOES NOT satisfy it.]\r\n" );
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document.write( "So A. is NOT compatible with 3y - 4x = 7\r\n" );
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B. 12y = - 9x + 28

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document.write( "Substituting (1,-1)\r\n" );
document.write( "   12y = -9x + 28\r\n" );
document.write( "12(-1) = -9(1) + 28\r\n" );
document.write( "   -12 = -9 + 28\r\n" );
document.write( "   -12 = 19  [So (1,-1) DOES NOT satisfy it.]\r\n" );
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document.write( "So B. is NOT compatible with 3y - 4x = 7\r\n" );
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C. - 16x + 28 = 12y

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document.write( "Substituting (1,-1)\r\n" );
document.write( "  -16x + 28 = 12y\r\n" );
document.write( "-16(1) + 28 = 12(-1)\r\n" );
document.write( "   -16 + 28 = -12\r\n" );
document.write( "         12 = -12 [So (1,-1) DOES NOT satisfy it.]\r\n" );
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document.write( "So C. is NOT compatible with 3y - 4x = 7\r\n" );
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D. - 4x - 3y - 7 = 0

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document.write( "Substituting (1,-1)\r\n" );
document.write( "      -4x - 3y - 7 = 0\r\n" );
document.write( " -4(1) - 3(-1) - 7 = 0\r\n" );
document.write( "        -4 + 3 - 7 = 0\r\n" );
document.write( "                -8 = 0 [So (1,-1) DOES NOT satisfy it.]\r\n" );
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document.write( "So D. is NOT compatible with 3y - 4x = 7\r\n" );
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document.write( "

E. - 56 - 24y = - 32x

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document.write( "Substituting (1,-1)\r\n" );
document.write( "    -56 - 24y = -32x\r\n" );
document.write( " -56 - 24(-1) = -32(1)\r\n" );
document.write( "     -56 + 24 = -32\r\n" );
document.write( "          -32 = -32  [So (1,-1) satisfies it. So we substitute the other point.]\r\n" );
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document.write( "Substituting (2,5)\r\n" );
document.write( "    -56 - 24y = -32x\r\n" );
document.write( "  -56 - 24(5) = -32(2)\r\n" );
document.write( "     -56 -120 = -64\r\n" );
document.write( "         -176 = -32  [So (2,5) DOES NOT satisfies it.]\r\n" );
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document.write( "So E. is NOT compatible with 3y - 4x = 7\r\n" );
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document.write( "So NONE of them are compatible with 3y - 4x = 7\r\n" );
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document.write( "Edwin

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