Graphing Calculator Graphing with the TI-83 Plus/TI-84 Plus I. Introduction The TI-84 Plus graphing calculator has greater memory capacity, is faster, and has a higher contrast screen than the TI-83 Plus model. Aside from these differences, the two calculators have virtually the same keyboards and they are keystroke-for-keystroke compatible. This is also true of the older TI-83 and TI-84 models. All TI-83 and 84 models have fifty keys, many of which perform multiple functions when used in combination. Each key has a symbol printed on its face. When a key is pressed the calculator does whatever is printed on the face of the key. This is often referred to as the primary function of the key. For example, the primary function of the ON key is to turn the calculator on, the + key performs addition, and raises numbers to the second power. x 2 In addition to their primary functions many keys have second, or shifted functions. These are the symbols written in yellow and green above the ke...