The axis of symmetry of a quadratic equation is x = –3. If one of the zeroes of the equation is 4, what is the other zero?

The axis of symmetry lies halfway between the two zeroes. Since the axis is x = –3, the zeroes must average –3. Let the other zero be r: (4 + r)/2 = –3, so 4 + r = –6 and r = –10. The other zero is –10, choice A.

AI-written and checked against the verified answer.