The statements that are true are: First option: All functions have dependent a variable Second option: All functions have an independent variable. Fifth option: A horizontal line is an example of a functional relationship
To get this answer you need to understand what a function is, a function is a relation from a set of inputs to a set of possible outputs where each input is related to exactly one output. If this is false, this is NOT a function. So, knowing that, the correct answers are, All functions have a dependent variable, All functions have an independent variable, and A horizontal line is an example of a functional relationship. So this 1st, 2nd, and 5th options.
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