Document.write function replaces the whole page with the text

Question

I am relatively new to javascript and I created a function to multiply two numbers together, but document.write replaces the whole page with the answer. I know

Answer 1

If you add an empty element like <span id="fillme"></span> to the document you can use this with var fillme = document.getElementById("fillme"); and then later assign content to fillme with fillme.innerHTML = answer;

Answer 2

You already know how to use document.getElementById() to retrieve the values of inputs on your page. So do something similar to update an element that holds the answer:

<div id="answer"></div>

...and then:

document.getElementById("answer").innerHTML = answer;

Simle demo: http://jsfiddle.net/V5R5h/1/