Basically, just line these numbers up like this:
62
+ 9
----
??
You'll see that the 2 and 9 lineup, so add them together first. That will give you 11.
We can put the first one in the "ones" place down, but the 1 in the "tens" place needs to carry over like this:
1_
+62
+_9
----
_1
Now on that left hand side, we have 6, with that new 1 that we carried over. Just add those together and you get 7. That gives us the number in the tens place.
So a final result of 71!