Substituting 25 for y in the equation y = (x − 11)2 gives 25=(x−11)2 . It follows that x−11=5 orx−11=−5, so the x-coordinates of the two points of intersection are x = 16 and x = 6, respectively. Since both points of intersection have a y-coordinate of 25, it follows that the two points are(16,25)and (6,25). Since these points lie on the horizontal line y=25, the distance between these points is the positive difference of the x-coordinates: 16−6=10. Choices B, C, and D are incorrect and may be the result of an error in solving the quadratic equation that results when substituting 25 for y in the given quadratic equation