Question 233235
Givn: {{{(1/r)= (1/s) + (1/t)}}}
The first thing I would do is get the part with s in it by itself.
This can be done by subtracting 1/t from both sides.
{{{(1/r) - (1/t) = 1/s}}}
Now multiply both sides by s
{{{s*((1/r)-(1/t)) = 1}}}
Then divide both sides by [(1/r)-(1/t)]
{{{s = 1/((1/r)-(1/t))}}}