Step 1 :The given equation is of a circle with radius 12. In a function, each input (or 'x' value) should correspond to exactly one output (or 'y' value). However, in the equation of a circle, each 'x' value (except the endpoints) corresponds to two 'y' values - one on the upper half of the circle and one on the lower half. Therefore, this equation does not specify a function with independent variable x.
Step 2 :To find a counterexample, we can choose any 'x' value within the range (-12, 12) (exclusive), as these 'x' values will correspond to two 'y' values on the circle. For instance, when x=0, the corresponding 'y' values are 12 and -12. Therefore, x=0 is a counterexample.
Step 3 :Let's confirm this by solving the equation for 'y' when x=0. x = 0, y_values = [12.0, -12.0]. As expected, when x=0, there are two corresponding 'y' values: 12 and -12. This confirms that the given equation does not specify a function with independent variable x, and x=0 is a counterexample.
Step 4 :Final Answer: The equation does not specify a function with independent variable $x$. A counterexample is $x=0$. So, the answers are "No" and "C. A counterexample is $x=0$".