npm i quadratic-solve

// ES6
import quadraticSolve from "quadratic-solve";

// commonjs
const quadraticSolve = require("quadratic-solve");

const solved = quadraticSolve(1, -4, 4); // arguments - (a, b, c)
console.log(solved);                     // output - [2, 2]

const solved = quadraticSolve(1, -4, 4);             // arguments - (a, b, c)
const verified = quadraticSolve(1, -4, 4, [2, 2]);   // arguments - (a, b, c, [root1, root2])
const incorrect = quadraticSolve(1, -4, 4, [2, 3]);
console.log(verified);                               // output - True
console.log(incorrect);                              // output - False