document.write( "Question 453353: what is the slope-intercept of 2x-7y=-24 passing through (9,11) \n" ); document.write( "

Algebra.Com's Answer #853384 by ikleyn(53614) $\"\"$ $\"About$

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\n" ); document.write( "what is the slope-intercept of 2x-7y=-24 passing through (9,11)
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\n" ); document.write( "\n" ); document.write( "        In his post, @mananth gives the answers: the slope is 0.29, x-intercept is 8.43.\r
\n" ); document.write( "\n" ); document.write( "        Both his answers are incorrect. His solution is incorrect, too.\r
\n" ); document.write( "\n" ); document.write( "        I came to bring a correct solution to this problem.\r
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document.write( "We want to find the slope-intercept equation for the line parallel 2x-7y = -24 and passing through (9,11).\r\n" );
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document.write( "In standard form, this line have the same left side\r\n" );
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document.write( "    2x - 7y = c    (1)\r\n" );
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document.write( "and some constant 'c' in the right side.\r\n" );
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document.write( "To find the value of 'c', substitute the coordinates (x,y) = (9,11) into equation (1).  You will get\r\n" );
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document.write( "    c = 2*9-7*11 = -59.\r\n" );
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document.write( "So, equation (1) takes the form\r\n" );
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document.write( "    2x - 7y = -59.    (2)\r\n" );
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document.write( "To get the \"slope-intercept form\", express 'y' from equation (2).\r\n" );
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document.write( "It is\r\n" );
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document.write( "    y =  + .\r\n" );
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document.write( "Thus the slope of the sought line is    and its x-intercept is  .\r\n" );
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document.write( "@mananth produced approximate decimals with only 2 correct decimals after the decimal dot - \r\n" );
document.write( "- but the problem asks about PRECISE values, not about their approximate values.\r\n" );
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document.write( "It is why the solution by @mananth fails and is incorrect.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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