x 2 - 40 x - 10 = 0 What is the sum of the solutions to the given equation?

Question

Accepted Answer

Choice D is correct. Adding 10 to each side of the given equation yields x 2 - 40 x = 10 . To complete the square, adding 40 2 2 , or 20 2 , to each side of this equation yields x 2 - 40 x + 20 2 = 10 + 20 2 , or x - 20 2 = 410 . Taking the square root of each side of this equation yields x - 20 = &#177; 410 . Adding 20 to each side of this equation yields x = 20 &#177; 410 . Therefore, the solutions to the given equation are x = 20 + 410 and x = 20 - 410 . The sum of these solutions is 20 + 410 + 20 - 410 , or 40 . Choice A is incorrect and may result from conceptual or calculation errors. Choice B is incorrect and may result from conceptual or calculation errors. Choice C is incorrect and may result from conceptual or calculation errors.

Question x-2-40