When it comes to plotting your equations, the right graphing calculator sure comes in handy. The perfect mathematical assistant, this must-have tool is essential when it comes to trigonometry, calculus, and the like. Generally, graphing calculators offer a wide array of functions. But, the one calculator that can solve all your problems is the Texas Instruments TI-84 Plus graphing calculator. This calculator can perform up to ten graphing functions simultaneously and is preloaded with 12 applications; so, it’s difficult to dispute this calculator’s value.