Description: Swap subtrahends in an inequality. (Contributed by Mario Carneiro, 27-May-2016)
Ref | Expression | ||
---|---|---|---|
Hypotheses | leidd.1 | |
|
ltnegd.2 | |
||
ltadd1d.3 | |
||
subled.4 | |
||
Assertion | subled | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | leidd.1 | |
|
2 | ltnegd.2 | |
|
3 | ltadd1d.3 | |
|
4 | subled.4 | |
|
5 | suble | |
|
6 | 1 2 3 5 | syl3anc | |
7 | 4 6 | mpbid | |