Metamath Proof Explorer


Theorem addridd

Description: 0 is an additive identity. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypothesis muld.1 φA
Assertion addridd φA+0=A

Proof

Step Hyp Ref Expression
1 muld.1 φA
2 addrid AA+0=A
3 1 2 syl φA+0=A