What do +(4,3) and -(4,3) mean? A plus or minus sign in front of a parenthesized pair of numbers

Question

I am trying to understand this logic in javascript

console.log(+(4,3)); //3
    
console.log(+(3,4)); //4
    
console.log(-(4,3));//-3

I know it's stupid question, but I am just trying to understand the logic under the hood