Question 735256
What is the slope of the line that passes through the points (7, -9) and (-13, -6) a. -3/20 b. 3/20 c.3/4 or d.5/2
<pre>
There are two ways to do it:

First way:

1.  Plot the two points:

{{{drawing(600,375,-15,9,-11,4, grid(1), circle(7,-9,.2), circle(-13,-6,.2),
 circle(7,-9,.25), circle(-13,-6,.25),
 circle(7,-9,.15), circle(-13,-6,.15)



 )}}}  

2. Draw the line:

{{{drawing(600,375,-15,9,-11,4, grid(1), circle(7,-9,.2), circle(-13,-6,.2),
red(line(-19,-5.1, 25,-11.7)),circle(7,-9,.15), circle(-13,-6,.15),
circle(7,-9,.265), circle(-13,-6,.265)
 )}}}

Draw a vertical rise (which is really a "fall" and a horizontal run from one
point to the other, so as to form a right triangle with the line:


{{{drawing(600,375,-15,9,-11,4, grid(1), circle(7,-9,.2), circle(-13,-6,.2),
red(line(-19,-5.1, 25,-11.7)),circle(7,-9,.15), circle(-13,-6,.15),
circle(7,-9,.265), circle(-13,-6,.265), red(line(-13,-6,-13,-9),line(-13,-9,7,-9))  )}}}

Counting blocks for the rise, the rise is 3, but it's -3 because it goes
downward from the line. Counting blocks for the run, the run is 20.

So the slope is rise over the run or {{{-3/20}}}.

--------------

Second way:

By the slope formula:

m = {{{(y[2]-y[1])/(x[2]-x[1])}}}

where (x<sub>1</sub>,y<sub>1</sub>) = (7,-9)
and where (x<sub>2</sub>,y<sub>2</sub>) = (-13,-6)

Plug in:

m = {{{((-6)-(-9))/((-13)-7)}}}

m = {{{(-6+9)/(-13-7)}}}

m = {{{(3)/(-20)}}}

m = {{{-3/20}}}

Edwin</pre>