Explanation
Correct answer: A.
Choice A is correct. It’s given that the graph of the equation is a circle in the xy-plane. For a circle in the form , its center is and its radius is . It follows that . Taking the positive square root of both sides of this equation yields . Therefore, the center of this circle is and the radius is . It follows that the x-coordinates of the points that lie on the circle must be within units of the x-coordinate of the center of the circle. Therefore, the least possible x-coordinate of a point that lies on the circle is , or , and the greatest possible x-coordinate of a point that lies on the circle is , or . So for any point to lie on the circle, it must be true that . Since does not satisfy this inequality, it is NOT a possible value of .
Desmos solution:
Note: For the given parameter value of negative 17, the regression’s nonzero error shows that no value for the remaining parameter makes the circle relationship hold.
Enter in Desmos:
Reviewed and rewritten by CookSAT
Why the other choices are wrong
Choice B
Choice B is incorrect. Since satisfies the inequality , it is a possible value of .
Choice C
Choice C is incorrect. Since satisfies the inequality , it is a possible value of .
Choice D
Choice D is incorrect. Since satisfies the inequality , it is a possible value of .