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JavaScript Object-Oriented JavaScript (2015) Introduction to Methods Finishing the Calculator


Implement the subtract method.

var calculator = {
  sum: 0,
  add: function(value) {
    this.sum += value;
  subtract: function(value) {

  multiply: function(value) {

  divide: function(value) {

  clear: function() {
    this.sum = 0;
  equals: function() {
    return this.sum;
    this.sum -= value;

1 Answer

Steven Parker
Steven Parker
229,644 Points

This might be easier than you think.

Take a look at the add method that has already been implemented. What the subtract method needs is very much like what is in the add method, but of course instead of adding (+) it will subtract ("-").

I'll bet you can do it now without an explicit spoiler.