Question 2193
{{{(1+x)/(2x)=9x}}}
<br> Cross multiply and we get...
{{{1+x=18x^2}}}
<br>
Now simplify and arrange the terms in descending order, like this...
{{{18x^2 - x - 1 = 0}}}
<br>
Now, plug it in the quadratic formula, which states {{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}, like this...
{{{x = (-(-1) +- sqrt( (-1)^2-4*18*(-1) ))/(2*18) }}} 
<br>
Simplify...
{{{x = (1 +- sqrt( 73 ))/(36) }}} 
MS