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

Need help on this question: Implement the subtract method. I can't figure out what I keep doing wrong.

Need help on this question: Implement the subtract method. I can't figure out what I keep doing wrong.

calculator.js
var calculator = {
  sum: 0,
  subtract: function(value) {
    this.sum -= value;
  },
  subtract: function(value) {

  },
  multiply: function(value) {

  },
  divide: function(value) {

  },
  clear: function() {
    this.sum = 0;
  }, 
  equals: function() {
    return this.sum;
  }
}

2 Answers

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

There's actually nothing wrong with your code. However, it is expecting there to be an add function, which you renamed to subtract. If you look immediately under the top subtract function... you'll find a second subtract function. Try resetting the code then take your line here:

 this.sum -= value;

... and put it in the subtract function they provide. And voilรก! Your code passes.

Thanks Jennifer! Got it.