document.write( "Question 983028: Solve the system of equations by graphing
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Algebra.Com's Answer #603834 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "First we look at the first equation:\r\n" );
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document.write( "The slope is -2 which has a 1 denominator \r\n" );
document.write( "The y-intercept is 9.  So we start at 9 on the y-axis\r\n" );
document.write( "and go down 2 units (since it's negative) and go right 1 unit,\r\n" );
document.write( "like this:\r\n" );
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document.write( "Then we take a ruler and draw a straight line through where\r\n" );
document.write( "we started and where we ended, like this:\r\n" );
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document.write( "Now we look at the second line,\r\n" );
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document.write( "The slope is .  The y-intercept is 2.  So we start at 2\r\n" );
document.write( "on the y-axis and go up 1 unit (since it's positive) and go right \r\n" );
document.write( "3 units,  like this:\r\n" );
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document.write( "[Wow! that pokes right in to the other line!]  Then we take the\r\n" );
document.write( "ruler and draw a straight line through where we started and where \r\n" );
document.write( "we ended, like this:\r\n" );
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document.write( "Now we can tell where they cross.  Right there where that poked\r\n" );
document.write( "into the first line.  If you draw a line straight down to the\r\n" );
document.write( "x-axis, you see that the x-coordinate is 3.\r\n" );
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document.write( "There's already a line straight over the the y-axis, so you can\r\n" );
document.write( "now see that the y-coordinate is also 3.  That means that the\r\n" );
document.write( "solution is (x,y) = (3,3).\r\n" );
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document.write( "We can now check to make sure it's correct by substituting x=3 and \r\n" );
document.write( "y=3 in both original equations:\r\n" );
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document.write( "So it checks.\r\n" );
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document.write( "Edwin

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