My bandsaw is currently under repair. I'm making a bookrack for my future daughter-in-law. She teaches first graders and this is for her classroom. The two sides are 30" tall, 12" wide at the base and appx 3" wide at the top. So I a piece of plywood appx 15" wide and 30" tall. I want to make a diagonal cut which will then give me both sides. I don't have a sled or a miter gauge big enough to hand 30". I doubt I'm making myself clear but is there a way for me to do this on my table saw relatively safely? I'm considering using a jigsaw with a level clamped to the plywood as a fence. Thoughts and ideas appreciated!

Thanks, Mike