document.write( "Question 105571: Find the slope of the line passing through the points (-9,3) and (4,-2) \n" ); document.write( "
Algebra.Com's Answer #76818 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given the points (-9,3) and (4,-2)
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\n" ); document.write( "To find the slope M of the line joining these two points you can use the formula:
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\n" ); document.write( "\"M+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"
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\n" ); document.write( "If you let the point {-9, 3) be the first point ... meaning its values of x and y are
\n" ); document.write( "\"x%5B1%5D+=+-9\" and \"y%5B1%5D+=+3\" ... then the second point is (4, -2) which means that
\n" ); document.write( "its x and y values are \"x%5B2%5D+=+4\" and \"y%5B2%5D+=+-2\" respectively. Then just plug these
\n" ); document.write( "values into their locations in the formula and you get:
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\n" ); document.write( "\"M+=+%28-2+-+%283%29%29%2F%284+-+%28-9%29%29+=+%28-2+-3%29%2F%284%2B9%29+=+-5%2F13\"
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\n" ); document.write( "So the slope is \"-5%2F13\"
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\n" ); document.write( "You might be able to speed up the process and to do it in your head by just looking at
\n" ); document.write( "the points (-9, 3) and (4, -2) and say to yourself:
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\n" ); document.write( "To go from the x value of the first point to the x value of the second point, I would go
\n" ); document.write( "from -9 to +4. This means that on the x-axis I would move from the left to the right 13
\n" ); document.write( "numbers or +13. At the same time, to go from the y value of the first point to the y-value
\n" ); document.write( "of the second point I would go from +3 to -2 in the y-direction. Since I am moving down
\n" ); document.write( "the change is negative, and the number of units to get from +3 to -2 is 5, so the change is
\n" ); document.write( "-5 units. This means the slope is -5 divided by +13 which again gives the answer \"-5%2F13\"
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\n" ); document.write( "Hope this helps you to understand the problem a little better.
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