does reduce work on an javascript object code example

Example 1: es6 array sum javascript

const arrSum = arr.reduce((a,b) => a + b, 0);

Example 2: reduce object to array javascript

var arr = [{x:1},{x:2},{x:4}];

arr.reduce(function (a, b) {
  return {x: a.x + b.x}; // returns object with property x
})

// ES6
arr.reduce((a, b) => ({x: a.x + b.x}));

// -> {x: 7}