Here why we use = sign, single + why not?

Question

int sum_up (int x, int y) {
x += y;
return(x);

Answer 1

BABLU TAUNWAL

x += y means x = x + y

If you use single + then it would be (x + y) which might be wrong because you have to assign (x + y) to another variable so (x += y) make sense because (x = x + y)