Description: An integer divides another iff it divides their sum. (Contributed by Paul Chapman, 31-Mar-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | dvdsaddr | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dvdsadd | |
|
2 | zcn | |
|
3 | zcn | |
|
4 | addcom | |
|
5 | 2 3 4 | syl2an | |
6 | 5 | breq2d | |
7 | 1 6 | bitrd | |