Theorem adddird

Description: Distributive law (right-distributivity). (Contributed by Mario Carneiro, 27-May-2016)

	Ref	Expression
Hypotheses	addcld.1	$$⊢\phi \to A\in ℂ$$
	addcld.2	$$⊢\phi \to B\in ℂ$$
	addassd.3	$$⊢\phi \to C\in ℂ$$
Assertion	adddird	$$⊢\phi \to \left(A+B\right)C=AC+BC$$

Proof

Step	Hyp	Ref	Expression
1		addcld.1	$$⊢\phi \to A\in ℂ$$
2		addcld.2	$$⊢\phi \to B\in ℂ$$
3		addassd.3	$$⊢\phi \to C\in ℂ$$
4		adddir	$$⊢\left(A\in ℂ\wedge B\in ℂ\wedge C\in ℂ\right)\to \left(A+B\right)C=AC+BC$$
5	1 2 3 4	syl3anc	$$⊢\phi \to \left(A+B\right)C=AC+BC$$