Question 454379
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Find an eqaution of the line containing the given pair of points.
(-7,-9) and (-4,-8)
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        The solution in the post by @mananth is incorrect both technically and methodologically.

        I came to bring a correct solution.



<pre>
First find the slope of the line  

    m = {{{(y[2]-y[1])/(x[2]-x[1])}}} = {{{(-8 - (-9))/(-4 - (-7))}}} = {{{(-8+9)/(-4+7)}}} = {{{1/3}}}.


Notice that  {{{-1/3}}}  is not -0.33,  as @mananth mistakenly states and uses.


Plug the value of the slope and the values of the coordinates (-7,-9) of the given point  
in the point-slope equation of the line 

    y = mx + b,

    -9 = {{{(1/3)*(-7)}}} + b,

    b = -9 + {{{7/3}}} = {{{(-27+7)/3}}} = {{{-20/3}}} = -6{{{2/3}}}.


So, an equation is

    y = {{{(1/3)x}}} - 6{{{2/3}}}.


It is the slope-intercept form equation.


Notice that it is absolutely different from that in the post by @mananth.
</pre>

Solved correctly.