Final answer:
Both the TI-84 Plus and the HP Prime Graphing Calculator can solve equations over complex numbers. The TI-84 Plus is known for its ability to handle a variety of mathematical tasks including complex numbers, while the HP Prime is an advanced calculator capable of complex number calculations. c is correct.
Step-by-step explanation:
The question asks which calculators can solve equations over complex numbers. Among the options provided, both the TI-84 Plus and the HP Prime Graphing Calculator have the capability to perform calculations with complex numbers. The TI-84 Plus, including the TI-83 and TI-83+ models mentioned, are widely used in high school mathematics and are known for their versatility in handling various mathematical tasks, including working with complex numbers.
The HP Prime Graphing Calculator is a more advanced device that also supports complex number calculations. On the other hand, the Casio fx-991EX can perform basic arithmetic with complex numbers but may not have the same graphing capabilities for complex equations as the TI-84 Plus or HP Prime. The Sharp EL-W516X also supports calculations with complex numbers but it may not have the same robust functionality as the more advanced graphing calculators.
In the context of solving equations over complex numbers, the mention of the TI-84 Plus and similar models throughout the references suggests that this calculator has the requisite functionality to assist the student with their question.