document.write( "Question 519378: What are three ways to explain how to graph 5x-8y=40?
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Algebra.Com's Answer #345554 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "            5x - 8y = 40\r\n" );
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document.write( "1.  Make a table of arbitrary values:\r\n" );
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document.write( " x |   y   \r\n" );
document.write( " 4 | \r\n" );
document.write( " 2 | \r\n" );
document.write( "-2 | \r\n" );
document.write( "-4 | \r\n" );
document.write( " Calculate the other variable values:\r\n" );
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document.write( "Fill in the table:\r\n" );
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document.write( " x |   y   \r\n" );
document.write( " 4 | -2.5\r\n" );
document.write( " 2 | -3.75\r\n" );
document.write( "-2 | -6.25\r\n" );
document.write( "-4 | -7.5\r\n" );
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document.write( "Plot the points:\r\n" );
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document.write( "Draw a line through them:\r\n" );
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document.write( "2.  Get the equation in slope-intercept form y = mx+b\r\n" );
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document.write( "  5x - 8y = 40\r\n" );
document.write( "      -8y = -5x + 40\r\n" );
document.write( "        y = \"5%2F8\"x - 5\r\n" );
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document.write( "The slope is \"5%2F8\" and the y-intercept is (0,-5)\r\n" );
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document.write( "Start at the y-intercept, draw a vertical line upward\r\n" );
document.write( "5 units (the numerator of the slope), and from there\r\n" );
document.write( "draw a horizontal line rightward 8 units (the denominator\r\n" );
document.write( "of the slope):\r\n" );
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document.write( "Draw a line through the y-intercept (0,-5) and the end of the vertical\r\n" );
document.write( "line:\r\n" );
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document.write( "3.  Find the two intercepts\r\n" );
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document.write( "To find the x-intercept, we substitute 0 for y:\r\n" );
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document.write( "  5x - 8y = 40\r\n" );
document.write( "5x - 8(0) = 40\r\n" );
document.write( "  5x - 0  = 40\r\n" );
document.write( "       5x = 40\r\n" );
document.write( "        x = 8, so the x-intercept is (8,0)\r\n" );
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document.write( "To find the y-intercept, we substitute 0 for x:\r\n" );
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document.write( "  5x - 8y = 40\r\n" );
document.write( "5(0) - 8y = 40\r\n" );
document.write( "   0 - 8y = 40\r\n" );
document.write( "      -8y = 40\r\n" );
document.write( "        y = -5, so the y-intercept is (0,-5).\r\n" );
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document.write( "Plot the intercepts:\r\n" );
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document.write( "Draw a line through those two intercepts:\r\n" );
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document.write( "Edwin

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