University math proofs. Do your work on paper or ipad and show every step

2. (a) Consider the numbers a = 243,b = 49 and c = 25. Find integers a and y such that abx + cy = 1. (b) Prove the following statement: "If god(a, c) = 1 and god(b, c) = 1 then there exist integers x and y such that abr + cy = 1. (c) State the converse and contrapositive of the statement. You do not need to provide any proofs