2x^2 −8x−7 = 0 One solution to the given equation can be written as (8− k)/4, where k is a constant. What is the value of k?
","rationale_html":"120 The correct answer is . The solutions to a quadratic equation of the form 2+ + =0 ax bx c can be calculated using the quadratic formula and are given by x =- b ! 2b 2-4 ac . The given equation is in the form ax 2+ bx + c =0 , where a = 2, a =- =- b 8, and c 7. It follows that the solutions to the given equation are x = 8! ^ -8 2h 2 - 2 4 ^ 2 h^ -7 h, which is equivalent to x = 8! 6 4 4+56 , or x = 8! 4 120 . It’s given that on ^ e h solution to the equation 2 x 2-8 x -7=0 can be written as 8- 4 k . 8- 120 120 The solution 4 is in this form. Therefore, the value of k is .
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