Question 1180654
.
Make a the subject of the formula in the equation s = (n/2)*(2a+(n-1)d).
~~~~~~~~~~~~~~~~~



            Please pay attention how I edited your writing to make the formula correct.



<pre>
You start from

    s = {{{(n/2)*(2a+(n-1)d)}}}.



Multiply both sides by  {{{(2/n)}}}.  You get then

    {{{(2s/n)}}} = 2a + (n-1)d.



Next move the term (n-1)*d from the right side to the left side CHANGING ITS SIGN.  You will get then

    {{{(2s/n) - (n-1)d}}} = 2a.



Last step multiply both sides by  {{{1/2}}}.   You finally get

  
     +---------------------------------------+
     |   a = {{{(1/2)*((2s/n) - (n-1)d)}}}.          |
     +---------------------------------------+


It is your answer.


You can transform this final formula further as you wish (using equivalent transformations, ONLY).
</pre>

Solved and carefully explained.



///////////////



Ignore the post by @mananth, since it is TOTALLY WRONG.