Answer:
10
Step-by-step explanation:
What is the missing addend?
We can fill in the blank with x
634+x=644
Now we need to get x to the other side
The rule to do this is what we do on one side we have to do the same thing to the other side
so if we subtract 634 on one side we also have to do that on the other side as well:
634-634+x=644-634
634-634 is 0
So it is
x=644-634
644-634 is 10
x=10
So the missing addend is 10
Hope this helps!
