Answers

2014-05-21T18:57:36+05:30
The slope formula is determined by rise/run. Our "rise" is y2y1, and our "run" is x2x1. Say you wanted to calculate the slope of two points: (x1,y1), and (x2,y2). If you draw a horizontal line that passes (x1,y1) and a vertical line that passes (x2,y2), you will see that it intersects at (x2,y1). The vertical line is our rise.
the distance between 
(x2,y2) and (x2,y1) Using the distance formula, which is:
D={(x2x1)2+(y2y1)2}^1/2
Substituting our coordinates into the formula:
D={(x2x2)2+(y2y1)2}^1/2
D={(y2y1)2}^1/2
D=y2y1
Therefore, y2y1 is our rise. Now for our run.  the distance between (x1,y1) and (x2,y1)
.
D={(x2x1)2+(y1y1)2}^1/2
D={(x2x1)2}^1/2
D=x2x1 Our run is x2x1
 Therefore, rise/run=(y2y1)/(x2x1).
Remember that 
m=rise/run.
m = (y2-y1)/(x2-x1)
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2014-05-21T19:12:32+05:30
Slope formula is m= y2-y1/x2-x1
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