Why in the prefix and postfix we write: Console.WriteLine(x+" "+y); ?

Question

this is the program:
int x=4;
int y=x++;
Console.WriteLine(x+" "+y);
output:
5 4

Answer 1

the initial value of x is 4.
y=x++ means "assign the value of x to y and AFTER THAT increase the value of x by 1".

so the value of y is 4 and the new value of x is 5.

the WriteLine says: write x then a blank space and then write y.

Answer 2

I understand this but why said (x+ +y) not(x+ y+)?