So with these two fractions you're gonna have to find the LCD (lowest common denominator) before you start adding them. With 6 and 8, the LCD is 24.
So with the numerator and denominator of
multiply them by 4. It'll look like this 
As for
, do the same except multiply by 3. It'll look like this: 
.
Now add the new fractions together:
A is the answer
So with the numerator and denominator of
As for
Now add the new fractions together:
A is the answer