Question 152602
You're definitely on the right track. But you don't even need to leave any denominators when you solve the problem:
{{{1/u + 5/(u-2) = 4/(u-2)}}} 
<br>Just multiply each side by {{{u(u-2)}}}
{{{u(u-2)(1/u) + u(u-2)(5/(u-2)) = u(u-2)(4/(u-2))}}}
{{{cross(u)(u-2)(1/cross(u)) + u*cross((u-2))(5/cross((u-2))) = u*cross((u-2))(4/cross((u-2)))}}}
{{{(u-2)+5u = 4u}}}
{{{6u - 2 = 4u}}}
{{{2u - 2 = 0}}}
{{{2u = 2}}}
{{{u = 1}}}