If your laptop has a mini display port, you can purchase one of these: https
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/www.amazon.com/gp/product/B0031SEMBQ/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1.
Plug the mini display port end of this cord into your laptops mini display port and plug the VGA end into the projector.
My wife's Dell XPS laptop uses this for her projectors needs all the time.