How to display an image on the javascript

Hi guys,

Im having a problem with my code:
If you go to www.searchtravelonline.co.uk
there is a searchbox on the left side and it has a button called "advanced search" in which is an image.. the problem is when u click on it .. it opens up the advanced option, but if you close it clicking on "hide" i goes back to normal but the button that was the IMAGE doesnt show anymore and it shows text instead..

im sending the javascript function...what i need to know i think is how to display an image instead of "<p>advanced search</p>"

thats my .js:

function showHideAnswer()
{
var numericID = this.id.replace(/[^\d]/g,'');
var obj = document.getElementById('a' + numericID);
var obj2 = "";

if(obj.style.display=='block'){
obj.style.display='none';
if (numericID == 1 )document.getElementById("q1").innerHTML = "<p>Advanced Search</p>";
if (numericID == 2 )document.getElementById("q2").innerHTML = "<p>Edit and recalculate</p>";
if (numericID == 3 )
if (numericID == 4 )document.getElementById("q4").innerHTML = "<p>Filter Results</p>";
{
obj2 = document.getElementById('d' + numericID);
obj2.style.display='block';
document.getElementById("q3").innerHTML = "<p>Read More</p>";
document.getElementById("e3").innerHTML = ""; }

}else{
obj.style.display='block';
if (numericID == 1 )document.getElementById("q1").innerHTML = "<p>Hide</p>";
if (numericID == 2 )document.getElementById("q2").innerHTML = "<p>Hide</p>";
if (numericID == 3 )
if (numericID == 4 )document.getElementById("q4").innerHTML = "<p>Hide</p>";
{
obj2 = document.getElementById('d' + numericID);
obj2.style.display='none';
document.getElementById("q3").innerHTML = "";
document.getElementById("e3").innerHTML = "<p>Hide</p>"; }



}
}


function initShowHideContent()
{
var divs = document.getElementsByTagName('DIV');
for(var no=0;no<divs.length;no++){
if(divs[no].className=='question'){
divs[no].onclick = showHideAnswer;
}

}
}

window.onload = initShowHideContent;
Edit/Delete Message