OG详解-OG6 数学1 Q3

Choice D is correct. Adding 53 to each side of the given equation yields k² = 144. Taking the square root of each side of this equation yields k = ±12. Therefore, the positive solution to the given equation is 12.
Choice A is incorrect. This is the positive solution to the equation k² -53 = 20,683, not k² -53 = 91. Choice B is incorrect. This is the positive solution to the equation k² -53 = 5, 131, not k² -53 = 91. Choice C is incorrect. This is the positive solution to the equation k² -53 = 1,391, not k² -53 = 91.