Metamath Proof Explorer
Description: Closure law for subtraction. (Contributed by NM, 26-Nov-1994)
(Revised by Mario Carneiro, 21-Dec-2013)
|
|
Ref |
Expression |
|
Hypotheses |
negidi.1 |
|
|
|
pncan3i.2 |
|
|
Assertion |
subcli |
|
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
negidi.1 |
|
2 |
|
pncan3i.2 |
|
3 |
|
subcl |
|
4 |
1 2 3
|
mp2an |
|