Question 457491
{{{y = a/(a-x)}}}
{{{y = (4/16)/(4/16 - 3/16)}}}
Multiply top and bottom or right side by {{{16}}}
{{{ y = 4 / (4 - 3) }}}
{{{ y = 4 }}}
---------------
{{{y = a/(a-x)}}}
{{{ y*(a-x) = a }}}
{{{ a*y - x*y = a }}}
{{{ -x*y = a - a*y }}}
{{{ x*y = a*y - a }}}
{{{ x = a - a/y }}}