Question

show that a positive integer 6x+5, where k ∈ n is also of the form 3m+2 where m ∈ n

Answer 1

6x+5=3x+3x+3+2.
=3(2x+1)+2.
=3m+2. ( let m=2x+1)

{ since x belongs to n then 2x +1 also belongs to n}