y = 76 y = x 2 - 5 The graphs of the given equations in the xy -plane intersect

Question

y = 76 y = x 2 - 5 The graphs of the given equations in the xy -plane intersect at the point ( x , y ) . What is a possible value of x ?

Accepted Answer

Choice B is correct. Since the point x , y is an intersection point of the graphs of the given equations in the xy -plane, the pair x , y should satisfy both equations, and thus is a solution of the given system. According to the first equation, y = 76 . Substituting 76 in place of y in the second equation yields x 2 - 5 = 76 . Adding 5 to both sides of this equation yields x 2 = 81 . Taking the square root of both sides of this equation yields two solutions: x = 9 and x = - 9 . Of these two solutions, only - 9 is given as a choice. Choice A is incorrect and may result from conceptual or calculation errors. Choice C is incorrect and may result from conceptual or calculation errors. Choice D is incorrect. This is the value of coordinate y , rather than x , of the intersection point x , y .

Question y-76-y