document.write( "Question 342318: How do you solve for x and y, and then graph these equations?\r
\n" ); document.write( "\n" ); document.write( "8x + 2y = 7
\n" ); document.write( "3x - 4y = 5
\n" ); document.write( "

Algebra.Com's Answer #244993 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
Multiply the first equation by 2 and add them,
\n" ); document.write( "\"16x%2B4y%2B3x-4y=14%2B5\"
\n" ); document.write( "\"19x=19\"
\n" ); document.write( "\"highlight%28x=1%29\"
\n" ); document.write( "Then use either equation to solve for \"y\"
\n" ); document.write( "\"3%281%29-4y=5\"
\n" ); document.write( "\"-4y=2\"
\n" ); document.write( "\"highlight%28y=-1%2F2%29\"
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "Convert both equations to slope intercept form, \"y=mx%2Bb\".
\n" ); document.write( "\"8x+%2B+2y+=+7\"
\n" ); document.write( "\"2y=-8x%2B7\"
\n" ); document.write( "\"y=-4x%2B7%2F2\"
\n" ); document.write( "Plot the y-intercept (\"0\",\"7%2F2\").
\n" ); document.write( "Then use the slope to calculate another point on the line.
\n" ); document.write( "Slope is change in y over change in x.
\n" ); document.write( "If \"x\" changes by \"2\", then \"y\" will change by \"2%28-4%29=-8\",
\n" ); document.write( "Another point on the line would be,
\n" ); document.write( "\"x=0%2B2=2\"
\n" ); document.write( "\"y=7%2F2%2B2%28-4%29=-9%2F2\"
\n" ); document.write( "(\"2\",\"-9%2F2\")
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "\"3x+-+4y+=+5\"
\n" ); document.write( "\"-4y=-3x%2B5\"
\n" ); document.write( "\"y=%283%2F4%29x-5%2F4\"
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "Plot the y-intercept (\"0\",\"-5%2F4\").
\n" ); document.write( "Then use the slope to calculate another point on the line.
\n" ); document.write( "If \"x\" changes by \"4\", then \"y\" will change by \"4%283%2F4%29=3\",
\n" ); document.write( "Another point on the line would be,
\n" ); document.write( "\"x=0%2B4=4\"
\n" ); document.write( "\"y=-5%2F4%2B3=7%2F4\"
\n" ); document.write( "(\"4\",\"7%2F4\")
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "Note the intersection of the lines occurs at (\"1\",\"-1%2F2\") as previously determined algebraically.
\n" ); document.write( "
\n" );