Answer - I have wrote out the chemical equation from the paper or photo above so you can just copy and paste, it makes it easier. Sorry if I got anything on it wrong, the handwriting was hard for me to read. (No offense.)
Explanation - Use this method to solve an non-redox reaction.
Let a, b, and c be the stoichiometric confluents.
CA, N2, CA3N2
(A) CA + (B) N2 ⟶ (C) CA3N2
Balancing CA atomy on both sides of the reaction.
(A) = 3C - (I)
Balancing N2 atomy on both sides of the reaction.
2B = 2C - (II)
Let A = (I)
From (I) C = 1/3
From (II) B = 1/3
Therefore, the balanced equation is: CA + 1/3N2 ⟶ 1/3CA3N2
3CA + N2 ⟶ CA3N2