在slideToggle中滑出fontawesome图标

I have made an imagebox, that when you click on it, a textbox slides down with the slideToggle effect. When i click on the box again to close the textbox, the slideToggle works. But when the text has slid down, i put a fa-angle-up fontawesome icon in the textbox, so visitors can close the textbox, instead of having to press on the imagebox again. Here is my I have made an imagebox, that when you click on