let persons = [
	{
		name: 'Sergey',
		surname: 'Honcharenko',
		age: 28,
		isMarried: false,
	},
	{
		name: 'Andrew',
		surname: 'Klymchuk',
		middleName: 'Anatoliyovych',
		haveAJob: true,
	},
	{
		name: 'Alexander',
		surname: 'Slobodian',
		sex: 'male',
		hasAPet: false,
	}
]

let parsedPerson = JSON.parse('{"name":"Elena","surname":"Mospanyuk","education":true,"height":170}');

console.log(persons.concat(parsedPerson));

// или

console.log(Object.assign(persons, parsedPerson));