Question 318800
Use the common denominator, {{{(u-8)(u+8)}}},
{{{(3u)/(u^2-64) + u/(u-8)=(3u)/((u-8)(u+8))+ (u(u+8))/((u-8)(u+8))}}}
{{{(3u)/(u^2-64) + u/(u-8)=(3u+ u(u+8))/((u-8)(u+8))}}}
{{{(3u)/(u^2-64) + u/(u-8)=(3u+ u^2+8u)/((u-8)(u+8))}}}

{{{(3u)/(u^2-64) + u/(u-8)=(u^2+11u)/((u-8)(u+8))}}}
{{{(3u)/(u^2-64) + u/(u-8)=(u(u+11))/((u-8)(u+8))}}}