Question

prove that if x and y are both odd positive integers then X + Y is even but not divisible by 4​

Answer 1

the statement you gave is false so it cannot be proven.

For example, 3+5=8,

which is even and divisible by 4.

Hope this helped.

Answer 2

Answer:

Let X and Y be of the form K+1 and K+3

where K is a even positive no.

Therefore ,

X+Y=2K+4

X+Y will be even as even no. is being added to K

but X+Y will not be divisible by 4 as it not nesecary

that K will be divisible by 4 as it can 2,6,10,14,18,.......