Change image on hover

Question

How can I change this exact code to do the hovering effect on mouseover?

I tried following some of the other questions and answers, but I could not really follow the

Answer 1

Here is a simplified code sample:

.change_img {
    background-image: url(image1.jpg);
}
.change_img:hover {
    background-image: url(image2.jpg);
}